I built my shooting board from two pieces of wood. The runway - the part the plane slides alonge - was made from UHMW plastic. This enables the plane slide smoothly over the hard plastic while cutting the wood piece on the baseboard.
I planed a small lip into the top board. This provides both clearance for the plastic runway covering and provides an area for cut material to accumulate off the runway. Strange but it helps a lot.
This picture shows the shooting board in use. I cut a one-inch thick strip of cherry and wanted to flatten its sides and insure they were mutually square. The cherry stock rests against the shooting board fence. As the plane cuts into the stock the stock is pushed into the fence.
Normally there is a cleat on the base of the shooting board to prevent the board from slipping when the stock pushes on the fence. I have not added a cleat to my board yet because I still have not figured out how I like using it yet. Instead I am using the clamp you can see in the upper right hand corner of the picture. That or I place the board on a low bench or the ground and secure the board with my knee. Sounds uncomfortable but gives amazing results.