Quote From the Film of the Hour:

Arthur: So, once we've made the plant, how do we get out? I'm hoping you have something more elegant in mind than shooting me in the head? Cobb: A kick. Ariadne: What's a kick? Eames: This, Ariadne, would be a kick. [kicks Arthur's chair; Arthur flails but manages to right himself] Cobb: It's that feeling of falling you get that jolts you awake. It snaps you out of the dream.