There is some useful info on shaving here:
Shaving pubic hair
Although it is mentioned there, I would like to stress the importance of going "with the grain". *If you don't shave in the direction of the hair growth in certain areas, particularly the pubic mound, you will get ingrown hairs which look awful and feel worse. *However, at least in my experience, it is safe to shave "against the grain" on the outer labia without fear of redness or itching. *You will probably want to do so in that area, since you can get a cleaner shave that way.