Be supportive of him/her.  All SAM referees are certified and required to take (at the least) a 14 hour course and pass an exam.  They get re-certified each year.  The referees control the game and many calls are judgemental.  The spirit of the Laws of the Game is to allow the game to flow:

• If the player is about to score, the referee may not take away an advantage.
• More experienced referees will make many "delayed" calls so they can see how a play is going to turn out.  Many coaches and spectators don’t understand why the call is delayed and begin to yell.

Abuse of the referee is not tolerated before, during or after a game.  To become a certified referee and improve the game yourself, go to the Maryland Soccer Referees website!