This is simple: you'll just have to think about an anime charcter that you think you could be compared with.

Example:
Someone looks at itself and says: I'm a guy with long white hair and have golden eyes.
Then that person starts to think about which anime character is he like, so he'd say... Inuyasha.

It's not obligatory to post a picture of the character.

If you see that you have similar characteristics of different characters, you may combine characters too!

Example: I'm a guy with grey hair and it has some spiky form (like a porcupine)... maybe I could be a combination between Zero and Ichigo.

Hope it was clear... enjoy!