All the advice is here.
I am sure you are probable overworking. If you are tense you will be inputting control movements without knowing it, and overdoing it when you do anything. Try chewing gum!
Set the power, set the attitude, set the ROD, TRIM. Sit back and admire. You should be able to fly hands off virtually all the way down. (this is a lot easier on large a/c as they are far more stable/faster/less affected by drift etc).
If your instructor allows, when you are stable carry on past minima to say 50 ft (or even lower) as this will sharpen up your handling no end.
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