Pulling very hard on leader lines up to get enough air to give a minimum structure in the kite, then release a bit and very slowly leader lines. But be prépared to slide 2 or 3 meters but the kite will not collapse at zenith.
And now a landing from edge of window as mentioned by Herman, at the end of video (2:12):
no secret or special skills : each time you read or try you will improve ! "I never lose. I either win or learn" Nelson Mandela
in high wind ; good preinflation by keeping the kite touching the ground is a safety prerequisite ; and not release fast the leader lines to avoid high speed and lift of the kite; then even your 2-3 meters slide on the sand can give you a certain style if you keep a smile for the audience