i need tips!
in both tricks!
my side throw (breakaway) it is always slant!, not straight!
and also in my sleeper always go in the sides of my finger not straight. (i always make my thumb up.)
(Is there a specific slipknot for tying a yoyo string?, or just a normal slipknot?)
(I didn't mind this problem in my side and front throw because i only throw for fun, but now i would take it serious even only in my throws!

)
Try placing your thumb on top of the yoyo and for the knot its just a normal knot with the string fed through it the just place your finger in the created loop-If the knot its made correctly the loop should get tighter when you are playing with the yoyo.(you may need tape for your finger becouse it can get prity tight) Going back to the throw, try throwing slower just focusing on the throw it self(then the power).
I find the more you make a muscle the better the throw.
This video might give you the idea for the knot.
http://www.youtube.com/v/MAJ5DSVleIM&rel=0Hope this helps.
Matt