I don`t really have many rules when it comes to using my stock, but I expect you to follow them.

They are:
Link me, in your deviation
Send me a link so that I can see your work
Do not use my stock in anything pornographic, racist, etc.

I will allow you to sell your work. After all it is your work, and I am happy to be of assistance.
I will also allow you to show off your work on other pages then deviantart, but I want to be linked.