A cool head is key, i mean ive played virtually all of my first season in snake and if you dont keep a cool head and you're panicking you wont get anywhere.
Next being smaller is a better advantage im 5"7 so that helps.
Getting as low as you can before diving and making sure that hopper and marker are above the ground otherwise you could get a hopper full of exploded paint.
Try to be aggressive when taking shots and moving up but you have to know when the time is right to go otherwise you'll be out before you peep out of your bunker.
2 characteristics not mentioned are more tactical. Once in the snake and more so after Snake 1or 2 you will attract guns .Staying alive is an underestimated quality.The bag side and centre will become easier to move just by your presence and the obvious countering of it.So sticking your head and gun up 5 seconds after you've arrived to mow them all down is not always the smartest move. Secondly when your coach/captain is calling the play,the ability to keep running the spot despite little success and still believing in it is important .Atop US coach once said his snake players best ability was "the memory of a goldfish". Not easy when you're game time is being compromised .