Once you are flying with the correct heading (calculated for crosswinds, of course) look out of the window and find some land feature in the distance which is roughly on the correct track and fly towards it. If it remains in the same spot on the windscreen then you are flying towards it.
You can now devote much of your time to doing the other things required safe in the knowledge that, if the feature it still in the same place on the windscreen, then you are pretty much on track.
Also, trust the work you put into your log before departure. If a town is supposed to appear 10 minutes into a leg then it probably will. I am always surprised at how accurate a well calculated log can be.