The easiest way I've found is as follows: 1. Capture the screen shot (prnt screen key, then paste to program such as paint/whatever). 2. Go to www.imageshack.com and upload the picture (doesnt require an account or anything, and you can have it resize to forum size on the options). 3. Copy the url it gives you for "direct link to picture". 4. Make your post, and use the image button on top. Enter the URL in the box that pops up. 5. Dance
Here is a pretty sick pin of my enemy i could have made it look better but my partner kept attacking so i had to take this picture :/ i have about 50 snipers, 10 tanks, enough medics and i have a saint coming. i would have had a lot more but ehhh :P