thanks to this vid i finally got the motion down. however, i cant keep my yo from fall down to my non throw finger....bummer

Create a hook and pinch that hook before the boing. Hope that helps....

By turning your finger over and allowing the string on your throw hand to fall into the same knuckle and curling your finger a bit will pinch the strings and prevent them from moving. Eventually just by pulling your fingers as far as you have learned, you can do it with a straight finger.

i now have a professional boingy

How about steering it- When I do it sometimes it works great other times the yoyo will rotate, typically for me, clockwise ( while looking down from above) and boing right out of my strings.
Not sure exactly what to do to counter act and keep it going straight -