To set a GE P7 oven to self-clean, turn the temperature settings to Clean, lock the door by sliding the latch to the right, and set the timer according to how soiled the oven is. Very soiled ovens need three hours to clean, but moderately soiled ovens only need two.
Once the cleaning cycle is complete and the temperature lowers, the oven door automatically unlocks and it is ready to be cleaned out by hand. The self-cleaning oven does most of the work by burning off debris and grease, but the inside still has to be cleared manually. Turn all settings off, and allow the oven to cool down completely before cleaning.