^ I think it really depends on the texture of your hair. Also, it varies by the type of hair cut you have. My friend and I both went to the same salon to get our perms done but the results were completely different. If you have a lot of layers going from the side all the way around, i would really recommend that you let your hair grow out because once the perm sets in.... it can look really messy (that's what happened to my friend- the middle part would poof up more than the bottom).
was it a digital perm? because my stylist said that it was good i already had layers because that's usually how they do the perm. once it's done, if it's frizzy they thin it out some but i doubt this will be the case since my hair isn't super thick.