Just start digging a hole in the floor of your basement. Once it's about 6 feet deep, start digging into the side of the hole, and you'll eventually tunnel out of the house. Just remember to at one point dig up to return to the surface, or you'll be stuck
"fore-ver"
-The Sandlot
Be discreet about it by putting the loose dirt in your pockets, and casually dump them out every time you're in the yard...like
Naked Gun 33 1/3.