Presence?

[JWP]

One thing that can really help, especially for younger, quiet refs, is to look like you are having fun on the court. Don't be a clown, of course, but don't be afraid to converse with the scorer, and to some extent, the players, and even in the right circumstances, with the coaches on a limited, casual basis. If something funny happens, laugh a little. It is supposed to be a game, after all.

There will be plenty of times when being serious -- very serious -- is crucial. But giving yourself a bit of a personality on the court can help give you a bit more presence.