Any golfer who has played at the Royal Golf Club will tell you that the greens present quite a challenge when it comes to consistently good putting.
The large and undulating nature of the slick greens demands the player's attention on every putt however small it may be. The first key to consistently good putting is pace. The greens at the Royal Golf Club are firm and very fast.
Golfers who are used to slower-paced greens will not have had to pay as much attention to the downhill or uphill nature of the putt, when in fact the slightest gradient change can dramatically affect the roll of the ball.
Without reading the effect the slopes will have on the run of the ball there is little chance of hitting it close. So when waiting for other players in your group to putt out you should attempt to read the putt from side on, your brain is an 'information recognition masterpiece' and even one quick look will be processed and you will instinctively change your perception of the putt, allowing you to produce the correct length of swing.
You may find that on the line of your putt you have to travel up and down slopes several times, quite often if you are travelling over a downhill slope, the ball may almost have to physically stop at the apex of the slope only to gather pace and continue its run to the hole. In this case you should place an imaginary hole on the apex of the slope and just putt to that point, forgetting about the actual hole!
But your work is not yet done. It's not sufficient just to focus on pace - on fast undulating greens the line takes on extra importance. You should always aim to produce a putt which is dying into the hole, and if the hole is situated near a slope, the ball will be practically falling into the hole sideways!
My experience so far is that most golfers do not start the putt wide enough, a putt dropping in to the hole at perfect pace will have travelled on a much wider arc than one at a slightly faster pace. Just as when looking at length you should try to imagine the putt rolling along its whole path, and pick out a point at the apex of the curve after taking into account both distance and direction. Try to have a couple of practice swings whilst looking at the apex, and see the ball travelling along that path.
Remember the key to good putting is information gathering, so try to look at the putt from a few angles at ground level, only then will you be able to produce the true line and length when preparing to hit the putt.