Sometimes I wander around and pick up whatever looks interesting, but often that gets overwhelming, and then I pick books out in advance, use the online catalog system to put them on hold, and pick them up from the hold shelf. That way I can consult my TBR list, check and see what's available, and choose a book from the comfort of my own couch.

I keep a list of interesting-sounding books that I want to read, which helps with this process. I use reviews, recommendations from friends, things I read on social media and hear about on podcasts, etc. to make my list. If the "blind date with a book" event worked well for you, I would see if the library has recommendations or book lists on their websites. Sometimes the individual library staff members recommend books, and you can figure out whose taste tends to jibe with yours.