It is far easier to control the ball if it is held with the fingertips rather than in the palm of the hand. Holding the ball from underneath with fingers spread apart and a firm grip should allow you to maintain control throughout the throw. The grip should feel natural and repeatable. A consistent grip will lead to consistent scoring.
The standard approach involves taking three steps toward the foul line, with each step in sync with natural arm movements that are similar to those used in normal walking. The bowler can begin with the foot opposite the throwing hand slightly ahead of the other foot (left foot for right-handed bowlers) before taking the first complete step. The throwing arm should move back with the second step and begin moving forward before the bowler begins the third step.
This third step is the "slide." The momentum from the push off of the second step allows the bowler to slide their leg during their third step. While this is happening, the throwing arm should be moving forward to release the ball, followed by a steady follow through.
The technique used by most bowlers is a "cross lane" throw, which is hard, straight, and comes from an angle toward the "pocket" between the head pin and either of the two pins behind it. Attempting to place hook or curve on the ball as seen in professional ten-pin bowling is ineffective in candlepin bowling. The small size and weight of the ball can make English difficult to control.
Ideally, the ball should roll off the fingertips, with the back of the hand parallel to the foul line. The ball should also be rolled toward the pins, and not chucked from a high release point. This causes bounce that reduces power and lessens control. In addition, the bowler should have his eyes locked on their target pins throughout the entire approach and delivery.
The Follow Through
An extended follow through helps the bowler maintain constant pace through her throw and increase accuracy. After release, the bowler's arm should be straight, with a locked wrist and elbow, and continue on a circular arc until it is past parallel to the ground.