Effect?

Can anybody tell me how I can get an effect like thesre? (The icons are here, because I can't get the link code to work. http://www.livejournal.com/community/icon_tutorial/777020.html)? I'd like to know how they got the icons so bright and crisp. I know there was a post about this before but I can't find it, and I have an icon that this would look perfect on.

Thanks everyone! :)