[blparent] adding texture to game pieces

[Eileen]

Hi,
I'm looking for ways to add texture to game pieces without a lot of
work. I have blokus which are colored pieces that fit onto a grid. I
need to add just enough texture to  tell the colors but not so much that
the pieces stop fitting into the grid. The pieces do not have an up or
down side and need to be able to flip face up or face down into this
grid. There are 24 pieces in each of the four colors so this is a lot of
marking to do. I'm stumped and would appreciate any ideas.
Thanks!
Eileen