uhh the cow bell thing would be a really bad idea

Let's see.........understand the Referee WILL make mistakes... it's actually part of soccer and it kind of goes against the american mentality. A lot of leauges have a zero tolerance policy and yelling at the ref will get you booted from the field...very embarresing.....
It's cool to yell GO and YEA and scream when they score but don't coach from the other side line. It's very confusing for the kids.
One thing that really confuses people is that in soccer, unlike baseball or football it's not a goal or out of bounds untill the ENTIRE ball is over the ENTIRE line....
In soccer the ref has an option called "play on". Even if there is an OBVIOUS penalty if there is no advantage gained the referee can just shrug it off and decide it isn't a penalty.. that one drives people wild some times
Theirs an off side rule that barely anybody understands but you won't have to worry about that for a while.... it doesn't fully kick in untill U-12 in most places
Normally what we did is have one parent bring some snacks and drinks.. orange slices or something on a rotating basis.
Now.. at the older ages the kids bring their own pretty much.
Always make sure they have a water bottle!
This may be my personal biggest pet peeve with parents. If your child is not going to be at practice or a game CALL!!!!!!! There is nothing more maddening to a coach then to get to a game and not know who is going to show up.
If I can spend 2 hours at a practice and blow every saturday morning for games I will never understand why a parent can't pick up the phone.