Instructions
Line up your character all the way to the right of the alley (or the left, if you're a left-hander), so you're by the gutter.
Aim the ball towards the pocket, which is the area between the first pin in the front and the second pin behind it. This will put you at a slight angle towards the triangle.
Throw the ball straight and with a lot of force. Not only will you be hitting the right area of the pins to encourage a strike, but you will have the power behind it to blast the pins away.