Newer gliders with weed-wacker leading edge reinforcements don’t like those reinforcement folded over so most pilots use some form of concertina or accordian fold. The book has an example, as does this video, but you see plenty of videos on the subject just by putting “concertina fold” in YouTube’s search bar. But there’s one that I really like for its speed. If I ever get a glider that requires concertina folding, I’ll probably use this fellow’s method. He gets it completely packed in 3.5 minutes. Enjoy!