V.W.
What I do is wear contacts while choosing frames. Otherwise I can't see what I look like! After I have tried on almost all the frames in the store, I try to narrow down what I think I like and then ask the technician who is helping me with my order for her thoughts. The store I go to actually has an extremely helpful person. Not all stores do. So be careful that you make a judgment call about the person before you listen too much to their advice. Women seem to do better at this, imo.
Also, there is usually a wait before you are seen by the optometrist. I use that time to begin trying on frames. Otherwise, I feel rushed afterwards.
When you find a general style that you like, try on several pairs in similar styles and different colors. Sometimes the color of the frame can make a difference. Sometimes it is whether the outer corners are rounded, squared, or cat-eye or sloped..... So try on lots and lots of frames. I always feel like I have tried on every frame in the store 3 times before I am comfortable with a choice.
Don't be shy about it.. glasses are expensive. And you will wear them everywhere.