As a PPL Student myself of 34hrs; what I can say is been there and working through it. I still occasionally forget the balance ball...but as the others say, a lot of it is feel and experience. My instructor suggested sitting in a chair at home and "work" the rudder pedals and the throttle as practice. As bizarre as this seems it helped. I kept on getting which rudder to use mixed up too...and my taxiing abilities were appalling
...however, one rudder incident and much practice later, now I can taxi whilst talking to my instructor about something entirely different...
My instructor showed me how much rudder was needed on take off when he took his feet off the rudder, totally leaving it to me...that drastic illustration really showed me how much rudder i needed to apply - and in which direction! He still has to remind me to look at the ball, so i am by no means perfect......just keep practising.
One of my problems was cockpit stance. I didn't realise how much it was affecting my rudder control until the CFI pointed out that my legs looked to stretched and advised on how i should sit. Silly little thing, and fairly obvious really, but once i changed my stance...my rudder control improved! Maybe discuss with your QFI?
The other things which I think has been touched on, is footwear. Now I know that some of the community will not favour this idea, (and am prepared for the consequences of saying so!) but I always fly in proper military flying boots. Thin soled, comfy, robust, warm and support in the right areas; perfect for feeling and working the pedals..and for grip when standing on the wing of the aircraft.
so, you'll get there...I am!