I had the pleasure of interviewing kirilee. Kirilee is a phenomenal seamstress with gorgeous action packed stock. She's branched out to cosplay and has some truly epic creations.
I first had a taste of stock back in 2005 (I had an account earlier than that, but it wasn't stock what I was posting). My friend Rebecca introduced me and then in about 2009, I remembered I had a DA account and wanted to give stock another try. So I set up my camera, put on some costumes I had around and posted them. I found the art works created were very inspiring, so I kept on going.
My favourite part about stock - seeing the artwork produced using your image. It is always a buzz to see how people interpret and use your initial image.
Everything and everything. Other stockers certainly do, but also, as a sewer I love doing stock with interesting garments.
Make sure you have a good light source. It reduces grain even with the very best cameras.
Also, don't be afraid to experiment. Try different poses, facial expressions, what you wear, angles for shoots etc. Just try 
Credit. It takes a moment. I know you want to show off your artwork, but please, we also spent hours getting that image for you to use.
Also, be respectful of the artists rules. If you are going to post on a different site, and the rules check BEFORE you post, please do this. Not AFTER.
My favourite part of cosplay is the craftsmanship and the performance aspect. In some ways, very similar to stock and I do find that they go hand in hand.
The one I've just finished making. It is Jennifer from Cloth Road (Manga).
In terms of stock, my favourite would be the "Red" series.
Triple chocolate with choco chip - of course!
