Rubber Bands on Wrists of Officials

[Brad]

I agree with Rut — keep it in your head.

There are plenty of things that you should keep in your head: Time remaining every time you blow the whistle (game / shot clock), AP arrow, team fouls (or at least which teams are in the bonus).

It's also good to remember a player if you have called a technical foul on him/her (since if they get a 2nd, they are gone). And it wouldn't hurt to remember that a certain player has 4 fouls, especially if the 4th one wasn't so great.

Overall, you should be aware of everything that is going on in the game and shouldn't have to rely on the table, the arrow, or a whistle in your pocket to remind you of that.