Rudder - set it and forget it on a stable tourer like a Warrior, but have a go in someting uncoordinated like a Citabra if you dont use your feet your all over the place.Get back in your spam can and feel how much more coordinated your turns are!
Mixture - lean any where never mind the 3000 ft old wives tale , Piper and Lycoming both recommend leaning on the ground ( remember full rich for take off). Read the poh for the technique recommended for your engine. Fuel might not matter to you now but some time you will want to go somewhere and best economy will be important. I fly an aircraft with a fuel flow guage and it make a hell of a difference 22gph full rich as opposed to 11.5 gph properly leaned. having said that as a student you should do as instructed and minimise work load til things happen automatically. Once you've wrapped your head round the basics read john Deakins articles on engine management on
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