2) Using the straight edge and the utility knife, score the two lines where you will be folding. These lines are represented by the dotted lines in figure 1. To fold, take two pieces of scrap wood and line their edges up. Then, place the sheet metal in between the two flush pieces of scrap wood, making sure to line the edge you just scored (using the utility knife) with the flush edges of the wood. Hold them all in place using the clamps. Then, place the third piece of wood on a flat surface like the table or floor, and bend the metal against it. Make sure before you bend, that the side you scored with the utility knife is bending outward not inward. You want a 115 degree bend as shown in figure 2
Use the plastic protractor as best as you can to check your work. After you have bent one side, switch it around and fold the other side. Drill the two holes in figure 1 using a bit with the same diameter as your machine screws.