Make sure you call a player nuetral only when you need to, its OK to look around a player while he/she is playing without calling them nuetral. Dont look at players when the game is on, I mean dont stand over them, when they are located by the opposition then its OK to watch them.
Watchout for hotspots ie when a player is going for a mug, I have seen so many arguments when already hit muggers are charging along bunkering.
You can lie down but vision and movement is restricted, it is best to work in a team of marshals on either side of the field. I am not joking if you have access to Radios use them on the small field it has been done.
dont be indecisive if he or she is out they are out, no ifs or buts.
You will get hit it will hurt, dont fall back just keep your cool and dignity and players will respect that, they need your support and all they want is to have a good day. watch out for goggle lifts go down on them like a ton of bricks it does work tell them they will go blind if they dont keep them on.
obviously wear bright clothing, pad yourself, drink lots of water and cover your crown jewels well.