You will quickly find that gamblers are a superstitious bunch.  There are several basic protocols of gambling, many of which satisfy these superstitions, that will make your experience at the table much more enjoyable.  You can read them now or learn them the hard way in the casino.

• Understand the rules of the game before you invest your hard-earned cash.
• Wait for a pass line decision before flinging your money and players card onto the table.  If you step up to the table while the shooter is tossing the dice, wait patiently for the conclusion of the hand before buying in.
• When you buy-in the dealer will give you denominations suitable for your buy-in level and the table minimum.  I feel it is also good to ask for $10 in white, or $1, chips as it shows a willingness to tip and starts you off on the right foot with the dealers.  More on tipping later. 
• You are usually not allowed to trade up in denomination except when you leave the table. If you have too many red chips and are betting over $25 then bet only red chips until you get your stack down through attrition. The dealers will pay you off in the largest denominations possible. If you bet $20 and win they often will take one of your red chips and give you a green. This is a subtle way the casinos get you to bet more. While you should have no compunction about asking to make change for large chips don't keep breaking one green chip at a time, it wastes everybody's time.
• When you are ready to leave the table, let the dealers "color you up."  This serves three purposes.  First it allows the dealers to exchange your chips for the highest possible denominations, thereby giving you fewer chips to carry to the cashier.  Second it keeps the smaller denomination chips at the table so there will be fewer game-interrupting chip replenishments.  Finally it allows the casino to track you winnings/losses for the purposes of comp calculations.
• Please do not drink excessively.  Yes, the drinks are "free," but there is nothing worse than a drunk gambler.
• Do not rebuke anybody for making sucker bets. Do not do anything that can be interpreted as being unlucky, like saying a number that would cause the table to lose. I know this sounds irrational but don't forget that gambling should be for fun so don't take from anyone else's experience.
• Do not chide the shooter for a bad toss, especially a 7.  Remember every hand ends with a 7.  You will throw one also, I guarantee it.
• Do not mention the number seven once the point is established.  Most only refer to that number as "it."
• Try not to hit any chips with the dice.  Superstitious players think this brings "it" out and they all lose.
• When the stick person passes the dice to the shooter it is time to end all betting and get your hands behind the chip rail.  Shooters can get very verbal if your hands are where they can be struck by the dice.
• Do clap and congratulate the shooter for a long hand.

As for the dealers, the same goes, you are tipping for their service at the table.  Even if the table is ice cold and you are losing you should still tip the dealers if they are making the experience enjoyable and/or more fun for you.