Trial Class

I have my first BJJ class coming up and I have no experience in martial arts. The gym has a few coed classes and a few ladies only ones, so I figured I'd start with a ladies night for the trial class and see how I like BJJ.

I will be going to a no gi class first, since I don't have one. I will wear a rash guard and spats/shorts that I got, and I know to wear flip flops off the mats.

I suppose I wanted to make a post to see what things I should look out for during my trial, and take in any advice. Is there anything I should know about no gi for my first class, or things that I should pay attention to (about the gym, instructors, etc) especially?

Thanks in advance!