Darts is a popular pub game that is also enjoyed at home and even played professionally. With darts, it is important to be able to throw with consistency--a consistent dart thrower is able to adjust his aim accordingly to hit his targets, while an erratic thrower can only hope to put the dart where he wants it. Increasing your consistency requires practice, even with the best form, but improving your form will greatly increase the effectiveness of your practicing.
Stand with your dominant leg forward and your non-dominant leg back. Align them so that a line drawn between the two would point at the dart board.
Keep the majority of your weight on your lead foot, but do not leave the rear foot weightless or off the ground, as this will make balance difficult and throw off your accuracy.
Lean forward slightly to reduce the distance to the board, but not so far that you find it difficult to maintain your balance.
Grip the dart with three or more fingers. More fingers will increase control during the throw, but can be more difficult to release without altering the trajectory.
Leave any fingers not holding the dart open and relaxed, not closed down against the palm.
Grip the dart just firmly enough to not have it moving in your grip--squeezing too tight will decrease consistency.
Pick a target on the board and aim for it. Even if you simply need a 20, pick a specific slice of single-20 to aim for.
Keep your body, with the exception of the throwing arm, still as you throw the dart and release it. The more still your body is, the more easily you can develop consistency in your throws.