I don't shoot the snake shot much. I mainly practice my snake shot so I can defend against the snake. The shot is a lot less physical than a pull shot is. If you are going to learn to use the snake, you might as well learn to shoot a front pin too.
To master the front pin shot you need to learn delivery. Set the ball up in the middle of the goal with defenders split. Practice circling the ball then delivering the ball straight into the goal. Practice circling the ball in both directions. As you get better knocking the ball between defenders tighten the defense. Make sure you switch from standard defense to reverse standard defense. When you can knock the ball in at will, splitting defenders, set up in front of the push and pull side goal, then just knock the ball in until you have the motion perfect.
The snake depends a lot on delivery too. Practice delivery until you can hit the straight in against tight defenses. Practice splitting defenses straight in against standard and reverse standard defenses. Once you can deliver the ball into the goal perfectly, add practice moving the ball then shooting. Delivery is key though. Practice knocking the ball into the goal exactly the way you want it to go. Set up over the goal and practice knocking the ball in until you can get an almost perfect delivery every time you shoot the ball.