ohoho i love this. Here are some things to do:
- when they are about to hit, reach into your bag to get something and on their backswing or a little before, slowly zip up the zipper.
- do the tiger stare, fold your arms, and don't talk during the round.
- ...or talk a lot, catch them off guard, make them laugh so they lose concentration
- before the shot, if they ask the yardage, give them the yardage, but then say, for example:
250 yards...no wait maybe 220...actually 200 yah 200.
This will make them nervous which club to choose (they probably can't hit that far but you get the point)
Also, if you know the course, with a combination of the yardage strategy, talk about all of the possible hazards, out of bounds areas, bad lies, stuff like that. If what you're saying doesn't scare them, then you rambling on and on will annoy the crap out of em.
- if they are in a bunker or have a tough lie, say something like "Don't chunk it." This will make them more aware of the possibility and more likely to actually do it, especially if it is one of their weaknesses and they are self conscious.
- Rush them, tell them you are behind and have to hurry (but be subtle, you don't want to come off as a worrywart)
- pull off an amazing shot (this is the best one). Practice a lot for one, but practice putting or some other shot that you use a lot in particular. If you hole one 30 foot putt, it'll make them pee their pants. (not literally of course).
- slurp a drink while they are hitting.
P.S. I do not recommend any of these except the second one, third one, and the second to last one. The best intimidation factor in golf is to be good. Finally, do not talk while your opponent is hitting. It doesn't get into their head it just makes you a jerk. Always say "nice shot" if they hit a good shot.