Here are some basic tips on golf etiquette
Etiquette:
Always be considerate and courteous of other players. Don't distract in any way such as talking or moving whilst a player is taking his/her swing.
14-Club Limit:
The USGA allows a maximum of 14 clubs to be carried in a bag. Under 14 is fine.
Tee Markers:
When teeing off on a hole, the ball must be behind the Tee markers, not just in front of them.
As It Lies:
Play the ball as it lies. This means you may not improve the way the ball is at rest. If you are on the green, you may mark, and pick up your ball to clean it, but while in the fairway, you must play the ball as it lies. See the USGA rule book for special circumstances like winter rules, obstructions, standing water, etc.
Away:
The term "Away" means the ball farthest from the hole is the one that is played first. The person with the lowest score for the hole has "the honors", and plays first on the next hole.
Bunkers:
If your ball lands in a bunker, always rake it after you have played your shot. The groups behind you will appreciate this. Since this is a hazard, you cannot ground your club prior to the swing. Practice swings are OK, as long as you do not contact the sand.
Out of Bounds:
If you hit your ball OB, there is a one-stroke penalty, and you must hit another ball. If you are not sure if the ball is OB, hit a "Provisional Ball" just in case. If you determine the first ball is OB, you continue on, and play with the Provisional Ball.
Water Hazards:
If you hit your ball into a Water Hazard, you may play it (could be messy), or with a one-stroke penalty play another ball from where you just hit. Option two is to drop another ball where the original ball entered the Hazard, incur a one-stroke penalty and play on.
Putting Green:
When on the green, never walk across another players line of putt. In tournament play, this will cost you a two stroke penalty. It is OK if the player is not on the green yet, but as a courtesy, watch your footing.
Have Fun:
Golf is a great game. So have fun at it and whenever possible - Leave the golf course in shape than you found it.