Originally Posted by Anon La Ply
I play by ear at first, but if I'm not hearing familiar patterns in a passage then I count until I can feel it. Counting is my fallback safety net.
This seems to be my approach at the moment as well. I'm also just joining my first band. I'm in the middle of trying to learn over 50 cover songs for our first gig in about 6 weeks. I think if I tried to count bars for each one I'd lose my mind. I kind of save that for the songs I'm not very familiar with. Luckily most of the songs we are doing are ones I have listened to for a long time and like so I think I at least have a sense of changes, etc.
On the other hand I do keep a notebook with each song listed in it and helpful notes for each song even if it says no more than whether it's a shuffle beat or money beat or whatever. If there's something tricky, I write it down so I can remember.