I use (and used on the Inter 17) two slightly different methods (Single line system - single handed.)

1, Up to about F3-4 and fairly flat water

a, (rounding mark to stbd) Come in of the wire and stand on the Spi sheet with your right foot, drop the traveller off and then stand on the mainsheet with you left foot.
b, uncleat and go hand over hand to drop the kite and at the right moment lift your foot on the sheet so all goes into the bag.
One thing to be carefull is that there is a point when the mainsail powers up (if the boat is not tracking) and you can have a bit of a hull fly. When standing, a quick hop to windward can save things (but you HAVE to know it will otherwise, stamp of the mainsheet rope with your LEFT foot and it will come uncleated - with practice). The other option is to just dump the mainsheet as the kite comes down.

2, windy and or lumpy

a, If on the wire, come in and sit/rest foot on the sheet
b, dump the traveller
c, get forward and uncleat, and then go hand over hand (but it is not as quick as standing up), at the right moment ease the sheet.
d, keep the mainsheet to hand in case the boat powers up and you fly a hull.