In my experience after kiting for 20 years, learning to foil was hard. You go from effortless competence to a rank beginner with all the embarrassment, bruises and cuts that entails.
For the average person that's normal in my experience.
Based on my time learning and watching others learn, the following pointers are most likely to help you succeed:
• Make sure the wind and water conditions are as good as you can get with approx. 12-15 knots of wind and flat water if possible. Crashes are slower in lighter wind.
• Use a reasonable sized board so that touchdowns don't submerge the board and throw you off. If the board can be thin as possible so it doesn't bob all over the place when you are getting ready all the better. Volume is not your friend.
• Start with a surf foil on a 600mm/24" mast which is known for its ease of use especially at low speed, something around 1000 to 1250 sq cm. Get a competent foiler to try it on your board and get the foil position on the board correct as well as the front foot position. If they say you've got a crap foil setup then maybe you have so you might need to try something else.
• A single front strap adjusted correctly so your foot can come out when you fall works best for me and a lot of people. It enables you to position the board easier when starting and can't snag a line like a foot hook.
• If you have the above points sorted, use a kite a size smaller than you would use on a twin tip. You don't need much power when you're up on the foil.
• Don't try and foil at first. Spend time getting used to riding the board along without getting up on the foil. It takes getting used with all that foil gear hanging off the bottom. If it keeps getting up on the foil when you don't want it to, move the foil back or the footstrap forward to keep the weight forward. (One of the locals at my beach spent almost the entire season doing this as rising up on the foil freaked him out!)
• When you're confident with the last point move your weight back gently and let the foil lift you up and then just as gently put the board back on the water. Repeat so you become comfortable with being the one in control rather than the foil.
• As you get comfortable make your time up on the foil longer until you're foiling for as long as you want both ways. One direction is likely to be easier than the other, you'll overcome this with practice.
•• You will get better with time and love foiling. It maybe all you end up doing with your kites which you may change to kites which suit foiling more
I did not enjoy learning to foil. It was frustrating and took up a lot of time when I could have been doing what I already knew. But it was worth it. I can now kite in ridiculously light wind and have fun. I can use inexpensive, small Peak4 kites and ride tiny waves and swell I didn't notice before.
Foiling can increase your kiting time 50% or more with suitable gear, and although you'll think I'll get on the TT or SB when the wind comes up, you may end up just using a 3m kite for wind over 20 knots on the foil and love it