Biggest help for me though really was using a music notation programme and tune-smithy to get the rhythm. Also, wikipedia gives a goodish explanation of polyrhythms and examples of how to count a 4 vs 3 rhythm.
OK, so clarification of that rhythm.When I have something like this, I break it down mathematically into fractions of a beat.The right hand plays every 0.25, and the left hand plays every 0.33.So you have:Left/right: 0.00Right: 0.25Left: 0.33Right: 0.5Left: 0.66Right: 0.75So let's take the left hand as our base, and put the right hand between it.The two hands play together on the first note.The second note of the right hand comes immediately before the second note of the left hand.The third note of the right hand comes roughly in the middle of the second and third notes of the left hand.The fourth note of the right hand comes immediately after the third note of the left hand.