Not to be a PITA, but the easiest IS to buckle your seatbelt. However, if, for some medical or physical reason that you cannot wear your seatbelt and don't want the chime going on incessantly, there is a wiring harness that connects to the seatbelt buckle under the seat. There is a connector that hooks the sensor in the buckle to the wires in the computer. If, by some happenstance that wire harness connector gets disconnected, the warning chime no longer works. So please be sure to make sure that the wiring harness is connected to the buckle to ensure that the chime works correctly.
Hope this helps.
Ken