You're Correct!

Make a pre-round plan of what you want to do on each hole of the golf course. What club you may hit, where you expect the ball to go and weigh up the dangers of what might happen in advance.

A simple example might be that there is water that starts at 200 yards from the tee on the left but there is out of bounds all down the right. The sensible option would be to plan to hit the ball down the left to the water but not take a club that will be hit far enough to reach the water. This is a very simple plan of risk versus reward.

The difficult part to planning in advance is what to do when a poor shot is hit on a hole, thus upsetting your plan. The simple answer is to also have a blow up plan. This is a maximum score that you are allowed to take on a hole and means that you are recognising the fact that you are potentially going to lose it mentally. For instance, imagine that the hole described earlier is a par 4 at 400 yards. You have a handicap of 18 which amounts to one shot per hole. You have already decided to try to get a five on the hole and lay up short of the water from the tee, using your extra shot as it is a difficult hole. Now you have topped the ball 50 yards from the tee and are feeling under pressure to get a five.

This is where a blow up plan is important as you have noted prior that you would not like to make more than a 7 (2 shots over your handicap is a good figure to use) on this hole. Now assuming that you will take two putts on the green, you have 350 yards to go to the green and 4 shots to get there. Suddenly 87.5 yards per shot doesnt seem that difficult and realistically you may be able to get there in three shots instead of four and only take a six. The point is that your mental state should have changed from anger and trying to catch up, to setting small goals to achieve a realistic target that will not ruin a round of golf.

Use this technique to avoid a blow up and remember that the game of golf is scored over 18 holes and that it is ok to give up one or two shots to the course on one hole but not six or seven.

This is a cardinal sin. You have hit a bad shot, accept it and move on. After all thats why the handicap system exists, to give a golfer extra shots to get the ball around the course. Hitting the next shot harder, taking a longer golf club than normal or taking on an unrealistic shot to get out of trouble usually only ends one way - badly. Collect your thoughts, play sensibly and move on. Remember, never play two shots from trouble.

A career shot is one that you are very unlikely to pull off and instead gets you into more trouble. Usually it follows a poor shot and looks something like this:
"I cant believe I just hit this shot into these trees, Im playing so well too. Right, well its only 170 yards to the green, I think I have a swing in these trees and Im sure I can get my 5 iron through the grass to that ball. There is a great gap for me to get through about 50 yards ahead...."

Golf is a game that pits you against the golf course. The attitude of trying to beat a playing partner means hitting it further or closer or better than them meaning that shots are taken on that are unrealistic, causing your scores to rocket. Play your own game and your own shots one at a time.