Pictures, descriptions, whatever. Do your best to describe the anime you want identified, and others will try to help you~
If you saw a picture on the internet or you have some brief descriptor but DON'T KNOW which anime it's from, post all the info you have here and people will try to help you identify it. Then you can watch your mystery anime.
Edit: I'm sure we've all had times when we found a cool anime pic and thought "I must watch that !" but had no idea what it was.
I hope this helps to clarify things~