There are some self-help chats (usually on Discord, IRC or Matrix) with other admins that you should join to get a feel of what typical problems arise and how to fix them. But it is usually not that much of a deal and you seem to be already on a good way.

Specifically for ActivityPub and other federated services it is important to know that even if there are only few people using your server the remote federated activities can have a quite significant impact on the performance of your server and RAM/Storage requirements.

Remote federated servers also usually "remember" who they talked to via special cryptographic keys and so on, meaning that if something goes wrong for some reason it might not always be possible to just delete everything and start new from scratch on the same domain as the remote servers will refuse to talk to your "new" server. Just something to keep in mind and another reason why backups are important.

If you're selfhosting already, you know how to deploy it. Are those services available in the internet via some domain? Having an SSL certificate with automated renewal is quite important. Make sure to update the machine the service runs on regular.

Backups! Having daily snapshots to be able to roll back if necessary is great. If you want to use your own hardware, I suggest Proxmox. If you want to rent a VPS, see if the cloud provider has something like that as well (will likely cost a little extra). Also, check the service's documentation on what data to back to in order to be able to restore on a new machine in case your server explodes. (3-2-1 rule). Shutting down the instance with no prior warning because of some error you can't recover from because of no working backup is the best way to spoil anyone's experience.

If you use docker, make sure to have it behind a reverse proxy and configure your docker ports to be bound to localhost only so you don't accidentally expose your database to the internet.

Think not only about technical deployment but also governance. Set instance rules and think how you want to do moderation. See if you have someone to help you with that.

Go for it! Set it up, fiddle around for a while and when you get comfortable, invite your friends. Just be upfront that there might be an occasional downtime for maintenance (which you will advertise a day before or so) every now and then.

I'm very comfortable in Docker and honestly most of the software out there in the Fediverse is weird. Like they make containerized deployments much more convoluted than they are supposed to be.

GoToSocial is maybe the least bad that I've tried so far. Most of the more popular ones are, IMO, really really bad on this front.

I've had their Stans counter this but then they point me to the process that they followed and it's like something out of a Hogwart's spell book compared to what most self hosted containerized apps are like.

There's also Managed Hosting: Hosting a Fediverse instance (a list of providers): "However, there are hosting companies that can take care of the installation and technical maintenance for you. You get a pre-installed application, mainly Mastodon, which is also technically maintained. You yourself are an admin and can do some things in the application’s admin menu, such as manage your own users. This way, you can also allow a larger group of people to access the Fediverse."