Using a belt sander or rough sandpaper, sand the ring to its desired shape and size. The ply is quite strong, so don't worry too much about keeping it thick for strengths sake. Then hand sand the ring using a fine sandpaper (something around 400 should be the last sanding). Now finish the ring. The finish should offer an aesthetic as well as functional purpose. For the colored ring, I liked something clear and shiny, so I used a hard clear nail polish. For the non colored ring, this is when I would lightly burn the wood.