For efficiency, try to keep your fortress layout compact and vertical. Dwarves navigate staircases much faster than hallways.

I typically dig a 2x2 central staircase for my forts and then dedicate each z-level to one thing/industry. For example, I'll have one level for my main stone stockpile as well as my mason/stone crafter/mechanic workshops and then have my furniture stockpile on the z-level below that so they don't have to haul finished furniture very far.

Hey welcome! Firstly, are you playing the steam version or the free version? Steam version I find to be much more new-player-friendly.

This is usually how I start my fortress, but it doesn't necessarily mean it's the right way:

1. Pick a location with some metal such as iron, and avoid aquifers unless you want an extra challenge when digging. . Pause the game and map out the basic structure of your fortress. Plot out where workshops will go, storage, and housing. Make sure paths are not too crazy. I found that time to travel affects the efficiency of your fort.
2. Decide how you want to get food and drink. I usually do a farm for food and brew.
3. Make a quarry somewhere to search and gather valuable materials.
4. And start forming some sort of defense early!!
5. Don't dig too deep too early in the game, you'll start introducing monsters into your fort which can wipe out your whole population.

I'm by no means a great dwarf fortress player, but hope this helps.

Edit: also don't sleep on pumps. I for some reason got it in my head early on that they were probably complicated. They aren't that bad, and make digging into aquifers very manageable.

If you're playing the Steam version, the tutorial does a great job at telling you the basics! Most stuff you're going to learn through trial-and-error; there's so much depth to the mechanics that it'd be impossible (and overwhelming) to cover everything from the get-go.

Here's how I typically go about it, as well as beginner tips that can be easy to miss:

1. Get all your supplies underground as soon as you can, right from the start. The very first thing I do is dig out a big room a layer or two down, then create a stockpile spanning the entirety of it. You're gonna set it to All. (You won't keep everything there forever; it's just to get it out of the way of thieves and wildlife for the time being.)

2. Make another room, this time creating a zone and marking it as a Meeting Area. Dwarves and animals tend to loiter around the wagon by default. Making this zone sets it as the new default area for everyone to bum around, safe and sound within the earth. An important note: Grazing animals (horses, yaks, cows, buffalo, etc.) need to eat grass or moss growing on the dirt to survive. When you set a Meeting Area, they will stay in it even if there is no grass, quickly resulting in their starvation. On the surface, create another zone set as Pasture, then assign your grazers to it.

3. Farming - both crops and livestock - requires dirt. Your dwarves only have dwarven crops available to them at embark, the most important of which is plump helmets. They MUST be grown underground. These crops can grow in dirt near the surface, but the soil is poor and yields will be low. This is okay for now! As you continue digging, you'll eventually breach the caverns, which have much healthier soil...but much nastier monsters.

4. Don't worry too much about making a beautiful base at the start. Your main goal for the first year is to survive and hopefully get a bit of industry going. Stonecrafting station for rock blocks, carpenter for beds and barrels, Brewer for booze, and, most urgently, Crafts for trade goods. You need to make as many rock crafts as time, material, and supplies will allow in order to trade for necessities come Autumn. The first thing you're gonna want to make at the Stonecrafting station is hatches, imo. Enough to cover up your entrance. This is the very bare minimum in defense and can be locked in the event of attack. You can't rely solely on this for forever, though - you'll have to go outside eventually, and migrants will need to come in.

That's about it for the start! Make sure you keep a careful eye on your supplies; it's all too easy to get sidetracked with construction and not realize you've only got three pints of booze left.

Since it hasn't been mentioned yet: The Wiki has a Quickstart Guide.

Number one rule is to remember that Losing Is Fun - it's not nearly such a brutally hard game to learn and understand now that the Steam version is out, but your fortress is a house of cards, and it can all come down very quickly. There's no 'win' condition, winning means doing what keeps you happy.

In order to keep going, you need to keep your dorfs (a) alive (b) at least somewhat happy - as luck would have it, the things that kill them also make them unhappy, so you can eyeball the state of your fort from the top-left, keep an eye on any really unhappy ones and fix what's troubling them.

My usual order of operations would be:

• assign some nobles - certainly a captain of the militia, and then make the bookkeeper / trader / manager the same as the expedition lead

• get access to some wood. If I've embarked somewhere wooded, just chop some down; if not, need to bring some with on embark, probs at least 30.

• dig down until I've got some access to stone. If that means going through some silt / sand / loam layers with aquifer, dig a bit wide and then construct wooden walls to keep the water out. Walls can be removed again later when you've built a drain of some kind at the bottom (the mist from falling water makes dorfs absurdly happy) but you don't really want to flood to start with. Damp stone can be smoothed to stop it leaking. You want to go at least one layer deeper than the last damp one, since it comes through the ceiling.

• decide where I want my farms to be, and dig it out. There's six underground plants and I find a 3x10 plot for each will support a lot of fort, so maybe a ten-by-twenty room. Plants grow in mud, which means either digging in a soil layer (very close to surface, not always available), getting some water in then letting it dry up, or digging down to the caverns and using the soil there (dangerous creatures live there! but if you've no surface trees, you're going there anyway). Filling an underground room with water is quite easily done with pumps if the surface is suitable (near a waterfall, so your farms can be above the river but underground), by building a floodgate and connecting it to a lever with a pump and then channeling out to the surface river (needs attention) or by connecting it to the aquifer layer and then walling it off when you've enough water. As long as you've at least one tile of 'depth 1' water, then it'll dry eventually - can expand your farm room until the water level falls, or pump it out, or drain it elsewhere. Designate farms, plant all the seeds you brought with.

While you're messing about with farms, you can get the rest of your starting base set up:

• prepare some defenses. A moat and a drawbridge (connected to a lever underground) is very effective - 2 wide and 2 deep if you're expecting the living, 3x3 if the undead. (But I would stay away from evil areas and towers if you've just started.) Pull the lever and close the drawbridge if anything arrives that you can't handle. Cage traps are massively overpowered - sprinkle them liberally. And doors and hatches can be forbidden against most incomers, plus dorfs are made happy by a good door

• build a (one!) trade depot. Can be underground to start with, caravans can get there. Goods wagons need an open 3x3 path all the way into your depot, without traps - you'll want that eventually as you scale, but it's a weak spot you'll need to deal with

• keep chopping down trees, because fuck the elves. You might have to dig down to the caverns for underground trees if there's few at the surface, but the caverns are dangerous so watch out. Only thing that can only be made from wood is beds, which you don't need loads of, but trees are an insult to dwarvenkind, so down they come.

• designate a couple of dorfs as military, and set them to 'always ready' but 'sleep in room at will' - this will make them wear all their gear all the time in case you need a quick response, but avoids the happiness and productivity debuff

• get some preliminary industry set up. You'll need stone, carpentry, mechanics, crafts, a still to start with. Wooden beds, bins and wheelbarrows; rock large pots (which work like barrels, but are generally better), tables, doors, 'thrones' (chairs), 'coffers' (chests), mechanisms, and mugs. I find it easier to allocate these in the 'orders' menu, build 3 if you've less than 2, and forget about it - also means that you can just move the workshops later and industry will continue when you want to consolidate. Also, add an order for 'brew drink from plants' - I usually set 'brew 2 when number of drinks is less than 10× your dorfs', but whatever works for you.

Get digging underground. I'd make space for the following:

• a dormitory, which has a few beds in it. Dorfs get unhappy sleeping on the floor - they really like having their own room, which you can build loads of later, but you want to avoid the happiness hit from sleeping outside or on the floor.

• an inn, which is a big empty room with some kind of chest in it, for mugs - dorfs really hate not having a mug. Store your booze in here.

• a dining hall, which I'd then assign to the inn. Put some tables and chairs in.

• a temple, which is essentially just a big empty room, and assign it to 'no particular deity'. Dorfs hate not being able to do religion.

• a small office for your bookkeeper - put a table and chair in, and assign it to them

• some industry space. You want to keep supplies, workshops and outlets relatively close together to minimise walking, but you don't have to go crazy - rock storage, rock workshops, rock finished goods and furniture. Kitchen products are absurdly overpriced for trade, lavish meals and milling products. But you'll need bags - 'process plants' to make pig tails into thread (farmers w/s), weave thread into cloth (loom), make cloth into bags (clothiers) which takes some lead time.

• when traders come, the highest priority stuff to buy is (a) all their cloth and leather, since it's cheap and hard to make, and you need lots of bags (b) all their plants meat and fish, to make into lavish meals to sell right back to them (c) anything else you think looks fun. Dwarves arrive to trade in the first Autumn - the amount you export to them affects the number of migrants you'll get, so feel free to pay over the odds. Elves arrive every Spring after the first year with loads of worthless shit and get offended if you offer them wood - seriously, don't buy their armour. Humans arrive every Summer with absolutely tonnes of stuff, but their armour won't fit you.

Once you've got all that, most of the pressure is off, and you can just progress as you like, have a laugh. You'll want a clothes industry to keep your dorfs happy (they hate wandering around naked) and a metal industry, which I find is easier done and also more dorfy by drilling straight down to the magma at the centre of the earth and melting/forging with it down there - wall off any holes you make in the caverns as you go, until you're ready for some Fun. But this is quite the essay already ;-) so I'll let you discover that.

Realised that I'd not written anything in my other comment about embark selection, which is quite important. For skills, I'd take:

• one appraiser / negotiator, based on whoever seems to have the best personality - they will usually become expedition leader
• two miners - you need to get digging quickly for safety's sake
• one planter/herbalist - farming is important, one expert will do
• one gem cutter / setter - takes ages to skill up, wastes loads of good resources doing so
• two sword user / shield user - but that's because I tend to set off in evil areas, probs don't do that if you're a new starter

For animals, I'd take:

• two male and two female cats, who will obliterate all vermin, which make your dorfs very unhappy.
• if not on an evil embark, two male and two female sheep, for milk (for cheese) and wool (for yarn, for making bags). Evil embark, we're going vegan for safety's sake

For items:

• refund the splints, crutches, stepladder and wheelbarrow, they're very easy to make and cost loads of points, for some reason
• if setting off evil, 2× iron shortswords, and copper 2× helms, breastplates, greaves and mail, 4× gauntlets and high boots. Dress your military immediately upon embark.
• if setting off in a swamp or other aquifer-heavy place, some of the cheap wood and stone, will help you get started on the digging
• keep the 2× picks and at least one metal battleaxe, to dig, and destroy trees
• loads of seeds, so you can kickstart your farms on embark. Plump helmets (food and drink) and pig tails (drink and thread, and also paper eventually) are the most valuable to me.

One of the things that I found helped a lot is to build a base with enemies turned off. Then you can explore the various different building mechanics without being wiped out randomly before you know how to build a military. Once you understand how the different craft types work you can turn the enemies on and start on the fun.