I'm a current leader of "Hachioji yoyomeeting".
This time, I submitted my favorite trick, braintwister,
to this contest.
-First, throw a yoyo as strong as possible and mount it on a string, just as normal brain twister.
-Along this, wrap the string around your right index finger.
This step is very important.
-Then, let the yoyo hit the string some times.
Please try not to weaken yoyo's spin.
A point of this step is to minimize the movement, using your left index and second finger.
If you get accustomed, you can do it faster. Good luck!