tomprice2k wrote:
Probably best demonstrating a couple of times then letting them try themselves
That's the best advice. I hope these additional tips are helpful:
Have your student lie on his back and place his palms on the ground by his head, fingers pointing down toward his shoulders. Then he should practice rolling up so that only his upper shoulders and palms are touching the ground. His feet should be vertically above his head. Unless he gets this down, kips will be very hard to do.
Then let him try to kip a couple times. Most people will flop around like a fish out of water for a few tries (try not to laugh

), then achieve a rough kip. Remind him that it's all about kicking his legs
up and forward. (The hand push and ab crunch just assist the motion for beginners.)
If he's still having trouble, kneel next to him and slip your hand under his shoulders as he tries so you can help him over.
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Once he can do an easy kip using his hands, have him practice the original rolling-up exercise -- but this time with his hands on his knees. When he has that down, have him push on his knees while he tries the hands-free kip. He may need your help with a little push on the shoulders again. Eventually he'll be able to do a hands-free kip without pushing on his knees.
I hope some of this is helpful!
p.s. - My very-traditional Vo-Binh-Dinh instructor had us practice several dozen kips during our warm-ups. It's a completely legitimate, traditional martial arts move, even if its practicality is questionable.