I wear cycling shorts and some sort of workout shirt... don't necessarily need a cycling jersey since no need for pockets or the zipper. As far as the look cleats go... it's possible... but I'd say unlikely. I've been to one class that had a couple of the bikes setup for look cleats but the vast majority of bikes are going to have a platform with straps on one side and a mountain spd on the other. I personally use some old mountain bike shoes for spin classes. The classes can be a lot of fun and an amazing workout, just depends on the instructor.