The sign for "hamburger"
is made by cupping your right hand on top of your left hand.
Now reverse the position of both hands.
HAMBURGER:
Memory
aid: Think of forming hamburger into a "patty" so you can BBQ it.
For additional memory aid, invite your ASL teacher to the BBQ.
Don't worry about the thumb position (open or closed). You'll see it both
ways. Here is another version of hamburger:
HAMBURGER: