what you will need
1) a squared piece of wood, scraps will do so long as the piece is true and square.
2) a saw.
3) marking knife.
4) a drill
5) and some clamps.
Step 1: Sawing
once you have a square piece of wood
from one corner to the other mark up.
then saw from the corner to the opposite, leaving 2 pieces like in the pic
Step 2: Use the Clamps Jaw As a Template
now place the clamp on the wood and draw around the clamp
do this twice
Step 3: Drilling
with your drill ( i used forstner bits for drilling.)
drill out the 2 markings you made earlier
until both bits of wood have 2 holes
Step 4: Finish
now you can clamp those tricky corners for example while making a frame or drawers
and that is that
thanks for looking
and be safe
take care all.