for some reason i can get all the intermediate tricks but i am having a time landing a double or nothing. the first loop around your non throw hand goes close to your back knuckle, then the second loop on that hand can go up toward your finger tip. it seems like i know how it is done but everytime i try to land it it misses the string away from my body. i don’t think i should have this much trouble with this but i guess it is easier said than done! i want to move on to other tricks but i have to do better than 2 out of 10 times landing this.
All I can say is to practice! 
Hi there, this trick takes a little while to get used to. Make sure you throw a strong breakaway and keep the yoyo as straight as possible when practicing this trick. When the yoyo is swinging around your fingers, try to keep the strings slightly apart from one another as this will help it land correctly on the string around your non-throwhand. You can also get into double or nothing by throwing a trapeze first and then practice getting the yoyo around your throwhand and back around to your non-throwhand. Hope this helps!
the videos here help alot and are good to watch much better than most. Try to when your making your landing sting thats when it goes around your non-thowhand make sure its farther out on the finger than the other giving it tons of space if you fly it right and can get a good lenght on the finger to yoyo to string thing than your all set to do the trick
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Also, make sure that when the first string goes around both of your fingers, that they are evenly spaced out, and are at the bottom at your fingers.
One tip that helped me was to have the yo-yo hit the string as close as possible to your non-throwhand finger. The more string length it has going around the finger the last time, the harder it is to hit the string. This means you have to hold your hands a little farther apart than you think you should.
Same trick works with trapeeze.