Leg break bowlers have more variations than Offbreak, but leg break is typically hard to master. Mastering leg break bowling can take you from a club cricketer to international cricketer just like that. Let me explain some.
Leg break(Big turn, Medium turn, Small turn)
Big Turn- Seem faces the point or backward point, when bowled, it will have maximum drift towards the opposite direction of your intended direction, when the ball lands it will turn big. It will however have NO DIP.
Seem Direction : Point or Backward Point
Drift : Maximum towards the opposite of intended direction
Dip: None
Bounce : Less than Medium, Small legbreak, bit more than Slider and Flipper
Length : Medium Good to Full Good
http://www.youtube.com/watch?v=zBbfPdXAIPI
Medium Turn- Seem faces 2nd, 3rd slip or Gully, when bowled, it will have some of drift, some of dip and some turn
i.e(Warne' Gatting ball)
Seem Direction : Gully, 2nd, or 3rd slip
Drift : decent drift
Dip: decent dip
Bounce : More than big leg break,flipper, slider, less than Top Spin, Small Turn
Length : Good Length
http://www.youtube.com/watch?v=LeLn8sEAKfE
Small Turn - Seem faces 1st slip or slightly towards offstump or little but outside of offstump, it will have little to no drift, lot of dip, it will land a bit shorter, when landed it will hurry on to the stump and it will have higher bounce than Big turn.
Seem Direction : 1st slip, Off stump, or little bit outside of Offstump
Drift : little to none
Dip: Medium to High
Bounce : More than big legbreak, medium legbreak, Flipper, Slider, less than Topspin
Length : Good Length to Short Good Length
First ball to Ranatunga
http://www.youtube.com/watch?v=rH0edm4vL40
Seem direction determines how much DIP, DRIFT and Bounce you get.
Higher the angle of the seam = More drift
Lesser the angle of the seam = More dip
Straighter the seam = Higher the bounce
Top Spin
Seem Direction : is at 90 degrees angle/up straight.
Drift : None
Dip : Maximum
Bounce: Higher than every other delivery
Length : Good Short length.
Will land shorter than expected, will bounce very quickly higher than normal and hurry on to you.
Googly
Seem : Straight, turned towards middle, or Legstump
Drift : Little to decent depends on where the seem is pointing towards(Higher the angle of the seam = More drift)
Dip : Little to decent depends on where the seem is pointing towards(Lesser the angle of the seam = More dip
Bounce : Little to decent depends on where the seem is pointing towards (Straighter the seam = higher the bounce)
Length : Good Full to Good Short
Unlike other deliveries, Googly is the only delivery that is bowled from back of the hand/palm
Flipper/Slider(Both are intended to do the same)
Seem : Straight(90 degrees) for Slider and Horizontal (0 degrees) for Flipper
Drift : NONE
Dip : NONE
Bounce : Lower than every other delivery
Length : Good full to Full
Wrist Position : Straight, facing the batsmen for Slider and Side of wrist facing the batsmen for Flipper
Unlike other deliveries, Slider and Flipper are spun with backward direction(Clock wise), opposed to other deliveries where the balls are spun in forward direction(Anti Clock wise). Slider is bowled with help of all 4 fingers, except pinky and it is pushed out from front of the hand. Need tighter grips, 4th finger still does major portion of the work. Flipper is bowled with help of thumb and 3rd finger(not the regular spinning finger). It is "snapped" out rather than pushed out like slider. You are basically snapping the ball out of your hand, like how you snap your fingers. Flipper comes a bit faster than a slider. Strong shoulders are required to bowl the Flipper, it is advised not to bowl Flipper if you don't have strong shoulders. Warne stopped bowling Flipper after 1996, adopted Slider. Slider is safer than Flipper.
If you can master all of this, bowl them accurately and you can spin about 6 to 8 inches on regular basis. You are wasting your time, should be playing International Cricket.