Carve out the clamps
Place your material on your wasteboard
Place the clamps around your material
Choose the hole that best lines up with the nearest threaded insert hole. The clamping force is perpendicular to the edge where the clamp meets the material being clamped. You want to have this force be directed as close as possible through the mounting bolt, so that you are mostly dealing with compressive forces, and minimizing torque forces at the bolt/washer.
Enjoy the carve.