Take the two pieces you are going to use, and then get some 2"x3"(2"x4")that are a foot longer than your plywood pieces. What ever the length is make sure that the 2"x3" are spaced about 10" apart. Glue the boards together and place the 2"x3" with the long side up. Set your clamps close to the plywood on the 2"x3" and clamp them. You should have a minimum of 4 clamps, 2 on each side. You are making a sandwitch. The pressure on the long end of the 2"x3" will make sure that they won't bend. No holes.
