The most cost effective flying you can do is when the plane is parked up on the ground before and after your lessons or perhaps at other times
When ever possible, spend some time just seated in the aircraft, practice radio calls, instrument scans, go through standard checklist items...pre-flights, EFATO, fire drills etc. Even finding your best seat position can enhance your flying enjoyment
Get as familiar as you can with the flight controls and aircraft systems; reference your text books with the actual aircraft and engine on the aircraft you are flying
This will give you a nice advantage when in the air during your early instruction, as you will be able to reach for the trim wheel or flap lever or what ever when asked to do so by your instructor (or later, as expected to do so by your instructor!)
Above all though, enjoy the privilege of flight
PS....put Stick and Rudder by Wolfgang Langewiesche on your Christmas list