When approaching in a high cross wind you have to crab towards the runway using the rudder, which has to be in the direction of the cross wind ie lefthand wind = left rudder, you hold this crabbing attitude until just before touchdown then you kickout (straighten the rudder). The amount of rudder will depend on the wind strength, but if you do a few practice landings with a cross wind you will very quickly get the feel of how much rudder is required.