I subconsciously separate hobbies into two categories, inside the comfort zone and outside the comfort zone. Do you want to fill your hours doing something you enjoy with people you like (or alone is good, too)? Or do you want to expand your horizons, meet new people (or learn to be content alone), and try something new?

That's a critical first question to answer, because any hobby can expand to fill the available time and budget.

And those are the next two questions, both important. Do you have long stretches of continuous time and an unlimited budget? Traveling is a great hobby that will also help you find new hobbies.

Do you have zero budget and unpredictable pockets of time? Crafting can be fun and an inexpensive creative outlet.

Think about what you like, who you like to be around, and when it makes sense to be doing it. Do you want to play Warhammer in a comic book shop with people who are way into it? Would you enjoy playing golf every weekend at the local club? Hobbies are a great way to challenge yourself and meet new people, or it's a great way to get all introspective and grow as a person in your spare time.