The Golden Rule..."Do unto others as you would have them do unto you"...is a good basis for golf course etiquette: treat fellow golfers and course property just as you would like them to treat you and your property.
Proper golf course etiquette, for the most part, involves just plain common sense, courtesy and respect.
Serious golfers, in fact any of us who play the ball "as it lies", become very upset when we find a course in bad condition because of negligence by previous golfers. Divot holes, footprints in the sand traps, trash on the fairways or greens can ruin a great game fast. So can the lack of basic courtesy towards fellow golfers. So, along with enough balls, remember to take The Golden Rule to the course with you each time you play.
If in doubt...ask
If you are unfamiliar with the course you're going to play, it's always a good policy to check with the Pro Shop in advance of your tee time to ask if they have special regulations you should be aware of before you hit the links - such as special regulations concerning appropriate apparel on the course, speed of play, special cart path rules, if walking is allowed, what type of spikes can be worn, etc.
Generally speaking, common sense-dressing applies. Most courses say no short-shorts, torn jeans, tank tops allowed. Many courses require collared shirts for men, casual slacks or appropriate length bermuda shorts for men and women...not too much "skin" showing. And more and more courses are requiring non-metal spikes these days. If you aren't sure about what you can or can't wear, check in advance with the Pro Shop.
Dispose of butts and trash properly
If you smoke cigars or cigarettes, don't throw your butts on the course. The golf course is one of the last places we have complete freedom to smoke. That privilege may be taken away if we litter the course with butts. It certainly doesn't look good and besides, what happens to that great shot when the ball just happens to collide with a cigar butt? So remember to dispose of butts, drink containers and any other trash, in proper receptacles on the course or in your cart.
Divots occur when your clubface takes a chunk of grass and dirt out of the ground on your swing. Divots happen as the result of good shots and as the result of poor shots. Either way divots are acceptable. Not replacing them is not acceptable. It is hard enough to hit a golf shot. And if you've ever attempted to hit a ball from a divot hole you'll likely never forget to replace a divot for as long as you play the game. So replace the divot in the hole, and tamp it in slightly. The roots will quickly take hold again and the grass will soon be growing normally.
You may spend a lot of time here...in the bunkers, or sand traps...and you might really mess them up trying to get out. So be sure to rake the bunker neatly when you leave. A neatly-raked bunker is not only more attractive, but also allows subsequent players to more easily "play the ball as it lies" in the sand.
Smooth ball marks on greens
Ball marks are small "craters" in the green caused by the impact of a spinning golf ball when it lands on the green. You should ALWAYS repair your ball mark when you get to the green. A properly repaired ball mark will start growing grass in a day whereas an unrepaired ball mark will take ten days before grass will begin to grow in it.
Safety on the course
The safety of those in your group, other golfers on the course, and spectators is very important. Always be careful when swinging a club. Serious injuries have occurred when golfers have been accidentally hit in the head with a club or ball. Do not stand directly in front of or behind any golfer getting ready to swing. Make sure the group in front of you is well out of range before taking your shot. If, by chance, the ball heads directly toward another golfer or group, be sure to yell "FORE!"... the accepted warning for 'watch out for the ball'.
Be particularly careful with children - golf clubs are not toys, and can in fact become a 'deadly weapon'.
This means not only foregoing displays of temper on the course, but also being respectful of those in your group and other golfers around you.
Don't move, talk, or stand too close to a player when they are taking a shot. Concentration is required, and noise and movement can be disconcerting.
Don't dawdle. Be ready to hit your ball when it's your turn. Keep conversation to a minimum and leave the cell phone behind - several minutes of "unnecessary talk" on each hole will add an hour or more to your round.
Keep the game moving - delays and slow play are aggravating to the groups behind you. If those behind you are playing faster than your group, then speed up your play if possible. If your group is slower because of less experienced players, then invite the faster group or groups to "play through" - or your group could skip ahead to the next hole.
Never step on the line of another player's putt. It can not only affect the lay of the tender greens grass, but also will cause the putting golfer to lose concentration and miss the putt. (Now, you wouldn't want that, would you!)
Have respect for all golfers
Golf is one of the few games that can be truly enjoyed by both men and women, young and old, healthy and physically challenged, and everyone "in between". Have respect, and encourage respect from golfing buddies, for all players - regardless of whether they're "in your league" or not.
Practicing these 'Golden Rules of Golf Etiquette' will help
everyone to have a more enjoyable and successful game.