it will come with time - but things that I found helped - get the trim right on the decent and it will fly itself in, when you get over the threshold look at the far end of the runway not down to the concrete, when you get over the runway and have cut the power try to fly the length of the runway without landing (you wont but it will improve your touch down a lot)..
ah and last thought - are you doing a lot of approaches in a cross wind at present? there is a lot of gusty cross winds about.. if so once again you judgement will improve with time as to the amount you have to turn into the wind to keep going straight.