how to bowl left arm spin

Now i will tell you how to bowl  left arm spin bowling.
first grip the ball same as off spin delivery as a right handed bowler does.
and rotate the ball as a off spinner and aim at middle stump . 
as the ball is released from opposite direction it will go as a leg break to right -handed batsmen.  
u can call this left-arm orthodox or chinaman.

how to bowl carrom bowl

The carrom ball is similar to the “Doosra” that Muthiah Muralitharan delivers. It is a delivery normally delivered by an off-break bowler but only it behaves like a leg-break ball. While Murali delivers it by turning the palm of his hand towards himself and by flicking his wrist, Ajantha Mendis delivers it differently.

2

The Grip To bowl the Carrom ball that behaves like a Doosra - Hold the ball as show in the picture with the seam facing gully. Place the index finger on the seam and the thumb below the ball. Essentially you’re gripping the ball between your thumb and index finger. Now place your middle finger folder underneath the seam of the ball (similar to how you get ready to srike a carrom with your middle finger), supporting the ball.

3

At the time of delivery Push your middle finger out (similar to the strike in caroms) by flicking it quickly. This causes the ball to not only spin like a regular leg-break but also provides it the additional lateral force to skid or shoot through causing further difficulty to the batsman.

4

Bowling other variations By using this concept of flicking your finger (or squeezing the ball out) with other grips you can get a similar spin/shoot combination on an off-break, leg-break, etc.