How did I miss this post?
Match play is all about psychological warfare. It is the ONE TIME it is you against an opponent and not the course.
If your opponent duckhooks one OB on a par 4, what is the new par for the hole? Five. Play as safe as possible to make a 5. He'll have to birdie to tie. You need to keep your gameplan flexible based on your opponents shots.
I love the suggestion to concede putts that come up short. I'm adding that to my arsenal. Subconciously brilliant.
On the greens, always mark. Never finish out. And don't let him tell you otherwise, but it is ALWAYS the furthest from the hole who has to play regardless of where each ball lies. You may be hitting out of a bunker from 5 yards while he is putting from 20 feet. He's out.
YOU CONTROL YOUR OPPONENTS BALL ON THE GREEN. Let's say you are putting from the fringe and his ball is a foot left of the cup. If he tries to mark, don't let him. You can use his ball as a backstop if you happen to be offline.
If you really want to be a prick (which I doubt you do), players that play a minimum of match play tend to hole out putts inside a foot out of turn instead of marking. The real prick thing to do is to say, "Could you remark that? I believe I'm away." Then hole your putt, and concede his anyway.
DO NOT ASSUME they are going to make a birdie. This used to get me in trouble when I first started playing match play. If these guys were great putters, they wouldn't be playing club events. When a guy stiffs one on a par 3, say 3-5 feet, and you miss the green, the tendency I used to have was to try to hole the chip. That is wrong. Make your par. If he makes the birdie, so be it. Just don't be so aggresively trying to hole out from a longer putt, or off the green, that you blow it 5 feet by and take a bogey. He is going to beat you every day of the week if you give him 2-putts to win from 4 feet. If he needs 1-putt to win, it's a different story.
STAND OVER A PUTT you would like conceded for a long time and look up at the guy. Then down at the ball, then up at the guy, then down at the ball. Then step off the putt and resume this again. Especially if it's a putt you'll make 95% of the time, like a 2-footer that he's not conceding for some reason. When you hole it after all that you say, "Whew, tough putt." Or you can say, "What? You got Lock-Jaw?"

The NEXT time you do this routine, make sure it's a little longer. Odds are he won't want to stand around watching you **** around and concede it.
If your opponent goes OB off the tee, you need to change your gameplan and play for bogey. If he only goes in the WATER, you still need to try to make par. The only change to your gameplan is to KEEP IT IN PLAY. Opponents WILL make penalty-stroke pars on shorter par 4's and most par 5's. Keep the ball in play. It's assinine to hit into the same hazard your opponent just did.
In match play an opponent ALWAYS has to tell you his correct amount of strokes during a hole when asked. When things are going bad on a hole for him, ask often, "How many you lying?" Make him think about score when he should be focused on his next shot. If he gives you an incorrect tally, and you KNOW he's taken more shots than that, ask him if he's sure. If he sticks by his original incorrect answer, inform him of his error, and notify him he just lost the hole. "Shall we walk to the next tee or finish out the hole for fun?" You NEVER have to hit a shot in match play WONDERING how many strokes your opponent lies. (Read RULE 9)
An 18-inch putt for a halve is 2000% tougher than an 18-inch putt to win a hole.
RULE 7-1a MATCH PLAY: On any day of a match-play competition, a player may practice on the competition course before a round.
So if it's not busy, feel free to warm up your putting on #18, or #9 of the actual course to be played. That will give you a truer feel for the speed of the actual greens. Plus it will give you the break for the actual putts you may have later. If the course is empty enough, go play a few holes. (Check with the committee to make sure there is no local rule prohibiting this. Though, if they do, have them look at Rule 7, Rule 1-3 and most importantly, Rule 33-1 and tell them to kiss your ass.

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Almost all of RULES that are 2-stroke penalties in MEDAL play are LOSS OF HOLE in match play.
There is NO PENALTY for teeing off in front of the marker in match play. If your opponent catches you, the worst he can do it make you retee it without penalty. (RULE 11-4a) I don't know why you would do this, but it's there if you want to use it. YOU can't choose to retee. Your opponent has to ask you to retee. And you know he isn't going to ask you to retee your bad ones.
If he plays fast, you play slow. If he plays slow, you play fast, or play even slower. If you lose the group ahead of you, mention it a lot. Make your opponent concentrate on ANYTHING besides his target.