Finding a new guild is a very hard thing to do. When my previous guild finally collapsed mid-BfA, I was lost because I had been with them since vanilla.
(Yeah, the original vanilla. Over a decade.) There are a few pointers I can give…
First… Know what YOU are looking for in a guild. This sounds obvious but not a lot of people put extended thought into it. When you’re considering this, consider not just activities but also guild culture (as an example, think: “what kind of jokes do you want to be hearing?”), what is the ability level of the guild versus your ability (you won’t fit in with a CE guild when you’ve never managed past heroic – be realistic about your ability!), the main location of the other guild members (tells you when people are going to be online most), and the size of the guild (a HUGE guild might have more people online, but be too large for any but a few to get to know each other well).
Second… Ask lots of questions. Now isn’t the time to be shy and you do not want to make any assumptions. Take time to think up a list of important questions and ASK THEM. If you want to raid heal, ask if there’s a raid spot available. If it’s super important you have people to play with on DayX, then specifically ask about how many people are on that day in a given week. If answers seem vague, don’t back down. Ask for clarification. Order of questions is also important for purposes of saving time. If there’s something which would make a guild a total no-go, ask about that first. You should ask to see their Discord, which will tell you a lot about the group too.
(As an aside to this, if you are interested in being in a raid, it would be super important to not just ask about raid times, but also the policies about missing scheduled raids, the loot rules, how raid drop BoEs are handled, what support is offered to the raid in the way of consumables or “class officers” who can help with knowledge gaps, and the scope/goal of the raid – for example, my own guild states ours as AotC focused with some dabbling in early mythic bosses.)
Third… Do NOT limit yourself to the server you’re currently on. This can be harder or easier depending on how many characters you have and you financial status either in or out of game. For small servers, it’s possible the pool of guilds is too small to have what you want. Look far and wide! I assure you that finding a great guild is SO WORTH IT. If you think you have found a great guild, battletag friending the guild members and cross server grouping for a couple weeks allows you to test how your personalities and active playtimes mesh. A guild that’s actively recruiting should be happy to let you make sure you’re making the right choice before server transferring. (If they’re not, to me that would be a hard pass, for example.) If you think you’re an omg awesome fit, pay to transfer just one MAIN CHARACTER to them. Other characters can follow after when you know for sure you have a winner. Don’t forget, character transfers can be bought with gold or RL money or a combination of both. For lesser alts, you can wait for a character services sale. (They’re uncommon, but they happen.)
Fourth… Don’t limit yourself to the in-game guild finder. While it’s possible to find guilds that way, it’s poorly designed, hard to search, and generally not the first place active guilds are recruiting. There is a bit of recruiting happening on the WoW forums, though it’s hit/miss. You’re really going to want to hit up social media. Look for Facebook groups and Discords where guilds are recruiting people!!
Lastly… Be ready to take your time. I can’t stress this more. Finding the right guild is going to take time. It took my friends and I several months to find the right guild, but we’re all very super happy in our choice. 