A cosplayer is successful as long as one can masturbate while looking at his or her picture. So:
- you should only choose sexy characters for cosplaying,
- you should not cosplay if you look completely different form the character you are attempting to cosplay, e.g. cosplaying Usagi Tsukino while looking like a tranny a.k.a. shemale represents a deep, excruciating and major fail.