I have found in my (so far) short flying career, that when a specific skill has been difficult to master, it's because I have not grasped, or am not using a fundamental concept.
For example:
taxiing - looking towards the horizon, rather than straight in front of the aircraft
turning accurately in the circuit - picking my horizon reference point on the wing before I commence the turn
bouncing on take off (tailwheel) - getting the stick forward before opening the throttle!
losing directional control on landing (tailwheel) - keep that stick right back!!!!
PFL's - getting and keeping the 30-45° view to the landing point
X-wind landings - know and understand (and don't forget!) what each of the controls really does for you on finals.
etc.
I'm sure some people's description of the 'key skill' will be different, but if you are struggling with something, then recognise that you have missed a key element, try to find out what it is and then focus on that element for a couple of tries - even if your instructor is helping with some of the other tasks.
As an example, my confidence in X-wind landings got a huge boost when my tailwheel check pilot took me to one of his mate's strip that had a 20-25 knot X-wind and made me approach and fly down the strip without landing. We probably could never have landed the thing without a ground loop at the end, but the exageration of all the control inputs required really helped drive home what everything was for.
Last of all - dream through each skill in your idle moments! Even virtual practice makes perfect (I think! - I'll tell you if I get there!
)
Don't give up!
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