Turn the riding mower off and remove the key.
Lift the operator's seat and locate the kill switch: a small, plastic box with two wires beneath the seat.
Cut the wires using wire cutters, then strip the ends of each wire with wire strippers, removing about an inch of insulation.
Braid the two wire together, then wrap the bare ends of the wires with electrical tape.
Lower the seat and place the gear in neutral. Put the key in the ignition and attempt to start the riding mower without being seated. The lawn mower should start; if it does not, lift the seat to ensure the wires are still braided together.