Here is a direct link to the rules on Wyrd.
http://wyrd-games.net/showthread.php?t=450
And some highlights:
In order to participate in the contest you must create an account on the Wyrd Miniatures website in order to submit an entry and to vote in the polls which will decide the winners of the contest. You are encouraged to enjoy the forums and participate, but it is NOT required in any fashion in order to enjoy the Wyrd Painting Contest.
and
The miniature cannot have been displayed in any form elsewhere on the internet or published mediums such as magazines. All contest entries will be displayed anonymously so as to give no one person an unfair advantage (this isn\'t a popularity contest) and thus there can be no signatures or watermarks upon them. No announcing on forums, webpage, blogs or any other type of medium about the type of miniature that you will be painting, nor concept sketches.
and
In order to submit an entry for the contest, go to the current contest gallery and upload your entry. As the gallery is set for moderation, your submission will NOT show up immediately but will instead wait for me to review and edit accordingly. When submitting your contest entry, please take the time to describe the miniature and its manufacturer as well as any other contest notes you wish me to review before editing.
Hope that helps. I do suggest reading the rest of the rules though, these are just highlights.