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Teeing up, how high? | Golf Monthly
Pink/Purple tees rock for me - though I used a single white one yesterday (dodgy knee meant it took over 5 mins to get sock on and 'normal' preparation went out the window!).
If you are using Yellow tees successfully, you must be swinging pretty flaf, or even descending, so the Driver loft is helping the launch. Pink/Purple, or even Grey/Orange should encourage an ascending swing. Orange ones are same height as Grey but much easier to find!
And general approach is that half the ball should be above the club face when Driver is placed on the ground, behind the ball. Yellow tee approach is heading the other way around! As the sweet spot of a Driver is above the middle (about 3/4 of the way up), you are not helping your chances of getting your best strike.