Ah yes. I've considerable experience on both ends of the towrope.
In my early days I had trouble following the tug, Dudley Steynor, a very very senior pilot who instructed at Wycombe during the 1940's! suggested that my left hand hold the right wrist, and this cuts down overcontrolling. That worked well for me.
As for following the tug on a descent, or if you develop a bow in the rope, yes, a cautious use of the airbrake will work to straighten things out.
Tug pilots don't always realise you have departed, seeing the glider out back with a wobbly wing mirror is not definitive! Whenever the tug waves you off, it may have engine trouble and if you don't obey you will find the glider is required to bring the rope home again! Don't worry about that, it trails nicely under the glider without hampering the controls! and it doesn't drag on the ground, but you may want to land long in case it catches the hedge....or simply dump it over the airfield when at a sensible height.
I was towing back a K13 from Wycombe with a PA150, and talking to Upper Heyford ... our progress into wind was so slow we didn't show up very well on their radar! (remember Mathias Rust and the Cessna in Red Square?)
At any rate, Heyford warned me that there would be a couple of fighter aircraft passing near our combination - no radio in the glider, so they were quite surprised, and got well out of position...not behind the tug, but beside me! with a tremendous bow in the rope. I was wondering what to do, but as so often, the answer was do nothing, carefully. And the glider sorted things out by gentle use of airbrake, back in correct tow position.
Correct position is judged by the glider pilot according to the tug position on the canopy of the glider. NOT by the wings on the horizon...that doesn't work in mountains or bad weather! ! ! !