Less instrument scanning
I find that the aircraft and gliders I have flown in the past 60 years, have flown better by themselves (once in trim) than my fiddling with the controls !
It is not necessary to scan the instrument panel in detail every 2 seconds, but an occasional glance at the critical ones (AIS, Altitude, engine rpm and temp, oil pressure and variometer in gliding etc) . I personally prefer the analog ones because relative needle positions in colored fields are immediately recognizable.
Your eyes should be outside the cockpit 99.9% and your head "on a swivel"
to scan the airspace around you for anomalies, such as other aircraft, which now include UAV's especially in the USA.
As is probably the most overlooked fact by students, it takes much time to reach proficiency and skill levels allowing you to spend less time flying the airplane and more time stategic planning route, method and execution.
Only the acceptance of a patient attitude makes students succeed. One step at the time ! The best way to learn to relax in an aircraft is to fly often and do many many touch and goes. It worked wonders for me.