I purchased a fat quarter from a LQS that was folded the neatest way. I hope I can explain it to you with these pictures. When fat quarters are folded like this, it makes them organized and easy to look at when choosing colors for a quilt.
fold the fat quarter twice, lenghtwise
[ATTACH=CONFIG]36226[/ATTACH]
then fold in half again
[ATTACH=CONFIG]36227[/ATTACH]
bring end with selveged edge up
[ATTACH=CONFIG]36228[/ATTACH]
tuck the folded edge into the selveged edge
[ATTACH=CONFIG]36254[/ATTACH]
this is what the finished fat quarter should look like
[ATTACH=CONFIG]36350[/ATTACH]