Are there any specific techniques or grips that can help me throw better?

A pencil grip is the most common. You can find it all over YouTube.  Regardless of how you end up holding your dart, keeping your index finger pointed slightly forward will help you avoid straying to the side of the 20. It's basic mechanics. If your fingers are 90 degrees to the dart, as you open your hand, you will end up pushing the dart to the left if you are right-handed, and to the right if you are left-handed.  Other than that, line up your shoulder and elbow, extend everything towards the dartboard, and throw with your wrist and forearm. Have fun.

I have been out of the game for over 5 years. My darts are fairly good by most standards. I'm hitting 8 and 9 hundreds on the soft-tip count-up games with 8 turns.  I don't play soft tip but I am told that is a good score. So you can take my advice or leave it.   I recently adjusted my thumb position so only the tip was touching the dart. This seems to have straightened out my throw. At the release point, the only two fingers on the dart are my thumb and index finger. Palm is facing the dartboard. The inside of my arm is facing the ceiling. I throw it from my shoulder. This ensures my shoulder is pointing at the target and as mobile as my upper arm.  I am not suggesting this is the right way to do things. I am sharing a recent change I have made which seems to have helped me. In the end, you will need to experiment and find what works for you. In most cases, the basics are the basics. 

Have you tried focusing on your head movement? Get in your stance and set your head before bringing your dart into position. With a proper stance and weight on your front foot, your head will not move. This is basic. Reach to the board. It is often suggested that one should point their elbow at the board. I find that pointing my shoulder works better. It eliminates shoulder movement.

Well, since there are not a lot of replies, I will use the site as a personal journal as I re-enter the game of darts. 

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