use landmarks.
fence, trees, power lines
practice, practice, practice

there'a a chalk line at my field. i use that also

i had the same problem at first also..
i was over controlling the plane, not giving it time to fly back during banking or truns.
my instructor made me do two 45 deg truns for trun around,
so the plane won't drift further and further away

i was also a little bit to slow to to level out ..so by the time i level out i wasn't parallel with
the chalk line , or the field. it gets further and further away this way too.
my instructor had me make minor adjustments with the rudder to correct the
flight path. after he told me level out faster for the millionth time

he also had me practice procedure turns for trun arounds.
i had to master this before before he taught me to land.
these procedures help me a lot . it help me practice left and right banking,
flying parallel to the fight lines more frequently other than just flying
in circles. i'll throw a loop in every so often to makesure my instructor
was still paying attention.lol

trun the stick in the direction that the wing is dipping to level the plane when
it's heading to you. this tip help me a lot.....i didn't have to think as much
anymore. it's r/c, i'm not sitting in the cockpit.

i also put big stripes on the bottom of my wing. i didn't get tired as fast
after that. i didn't have to try to focus as hard anymore.