Summarize the following:
Shake the bag a little to let the chips settle at the bottom of your bag. Set your bag of chips on its back so that the label is facing up. Smooth down the top portion of the bag 3-4 times until its flat. Work from the bottom of the bag to the top to remove the excess air from the bag. This method is easy, but it won't keep the air out unless you store the opening under a heavy item. The more air there is the bag, the faster your chips will become stale. Take your bag and flip it upside down so that the folds are on the bottom of the bag. Your bag of chips should stay folded automatically. To keep the folds from unraveling over time, place a vase, bowl, or something heavy on top of the folds to keep them weighed down. Your folds may slowly come undone if you don't weigh them down at all.

Summary:
Lay the bag down and smooth the bag out to remove air. Store the bag upside down on top of itself.