You need a long runway somewhere and a willing instructor.
If the approach is sound, bad landings are almost always are caused by:
a. A lack of feel for where the runway is,
b. The need to rush the landing before you run ouf of tarmac.
With a long runway available you can attempt a few landings where you hold the aircraft off for as long as possible in the certain knowledge there is no risk of running out of runway. You might well be amazed at just how quickly the aircraft stops after in finally settles. You will also develop a feel for where the runway is because the brain learns the perspective by frequent exposure to the visual ques. If you havent many landings under your belt and they have all been a bit rushed the brains exposure to these visual ques is short. A loooong holdoff will give your brain more visual ques that it gets in 10 rushed landings so doing it this way also represents very good value for money.
I know it works, tried it with quite a few and they are always amazed at what an effective cure it provides. In fact if you start flying faster aircraft (or at least aircraft with a faster approach speed) it remains just as effective when you find yourself rushing the landings because you are worried about running out of tarmac. A short session of going back to basics soon sorts it out.
Good luck.