It's not too hard.
But I'm wrong about this, anyone can feel free to correct me as I haven't played in ages myself.
There are already 2 "players" that will move the pieces.
So if you're one of the chess pieces, this is what you need to know if you're any of these.
Pawn: Move up to one or two spaces forward or backward. Diagonal only to capture another piece. IF a pawn reaches the enemy side, it can become another piece like a knight.
Knight: Moves ONLY in an L formation (for example, one right, two up)
Bishop: Moves ONLY in a Diagonal line.
Rook: Moves ONLY in a line formation (up, down, left or right) even to capture another piece.
Queen: Moves in all directions, even diagonal.
King: If captured or cornered, the game ends. Able to move in all directions (but I think there's a limit on how far he can go?)
So just remember this and you should be fine. =)
Hope this helped.