I read to trim a quarter inch. My parents wouldnt let me get my hair cut and as a result i had the worst split ends ever and it wouldnt grow past my shoulders. Earlier this year i got it trimmed every month for a few months and it was growing like crazy and looked pretty good, except that it was dyed. So now im trying again with my now natural color. Wavy hair is the worst to deal with, cuz the stylists will razor it and that eventually deflates and frizzes it.