Practice does not make perfect if your form is all wrong. There is a technique to throwing the perfect dart that will have to be utilized every single time. Your form and technique is what makes an accurate shot happen.
Understanding the basics of throwing is very important. Your arm determines where the dart is going to hit and once you learn and perfect this, you will be able to hit where you want to everytime.
The parabolic curve is how the dart will fly through the air. This is the same curve that bullets and baseballs fly on. Achieving this curve is by holding your arm straight out, bending it at the elbow. Keeping this form and holding it will lead to success.
With the dart in your hand, take aim at where you want it to go. Keep focusing on the spot you picked and not the dart itself. Once that is decided, make sure to keep your shoulder straight at all times. Release the dart, following through with your arm all of the way. When you start to throw, go slower and then gradually speed up.
Once you get the form down of how to throw the perfect dart, you will be doing it every time. Your technique will get better and better the more that it is used.
Trying to do tricks, like spinning or twisting the dart, will interfere with the parabolic curve and the dart will most likely not land where you intend for it to go.