Don't feed fhe rats. All. Coaches are rats. Don't bait them. Resist the urge to make sarcastic remarks. At least until you have built a reputation as a solid umpire. Follow the guidelines set forth in the rule book: Be impartial, courteous, firm, and fair (paraphrasing) and thereby compel respect from all. (Right Yoda? @UMPJM)
Do your job. Earn your pay. Study the rules. Study the game. Learn your craft. Listen more than you talk. Ask questions HERE. Take each game, each inning, each PLAY as a learning opportunity. Self evaluate and solicit advice from ppl you trust. Go to a real camp/clinic. NEVER SAY ANYTHING TO A COACH OR PLAYER THAT WOULD RESULT IN THEIR DISCIPLINE IF THEY SAID IT TO YOU. When you deal with team personnel, be friendly. But remember, theyre not your friend. The ONLY friend you have on the field is your partner.
Don't take to heart any praises you might receive any more than you do any ridicule you receive.
@Slim Jim
Jocko's post in Having Rabbit ears vs letting it go to far was marked as the answer