The Owner's manual for the engine(s) should show the port for a water hose pickup. If you don't have the manual, buy one.
Jets are an entity all in themselves. Sending water to the engine with it not running can send water to the cylinders and thus hydrolock the engine and thus turn a good engine into crap.
Anyone that knows anything about these motors understands that you start the engine first, turn on the water, and then turn off the water and then lastly turn off the engine.
If you screw up and forget the proper sequence, simply pull the spark plugs, remove the seat, hit the starter and watch the fountain of water shooting in the air coming from the waterlogged cylinders......