You will need scissors, something hard and rectangular (I am using a tablet lol), duct tape (obviously), and cardboard.
Step 1: Trace
Trace along your rectangular object and make the shapes above. I traced the correct lines with a marker. You need the front, back, sides, bottom, and lip. (I forgot to trace the bottom with the marker)
Step 2: Cut Out
Step 3: Tape Together Like This...
and then cover completely with duct tape. On the part where it is taped in random places, you don't need to do that, there were holes in my cardboard.
Step 4: Cut Off Excess Tape
Do your best not to cut the cardboard.
Step 5: Messed Up
cut off triangle flap and tape it to a small cardboard rectangle. cut off excess...sry for mistake.
Step 6: Tape on the Flap
Step 7: Cut a Small Piece and Rip It in Half, This Keeps Your Flap Down.
Step 8: Ta-Da!
tape the flap down and done!