Rules for the player who owns a passed pawn
1) Control the square directly in front of the pawn;
2) Trade all the minor pieces so that a Knight or Bishop can't block the pawn;
3) Keep the Queens on so the opponent's King won't feel comfortable rushing up to combat your pawn;
4) Keep at least one Rook on.
I have just found this in a demo chess mentor course.to see how the rules can be implemented,checkout this useful mentor course :http://www.chess.com/chessmentor/view_lesson?id=2901 IT'S A DEMO COURSE,THANKS TO CHESS.COM.
Hoping that you will enjoy it.