Literally the best part with doing the manuvure you can go really slow, just take your time, if another car has to wait a minute for you to do it then so be it, that 1 minute lost for them is another 50 years of driving for you.
When doing any manuvure just ensure your clutch control is so accurate, just little nudges up and down to go back and forth, ensure you are alligned correctly, correct steering and always make sure you do your 6 point check and the stupid looking swingy thing where you just look over each shoulder quite aggresively.
Hope some of that made sense and helped you out.
I am on about 11 hours now and im booking my test for next month.
I also have my own car so i can private practice so if you can get insured on a parents vechile or any car then it would be great for you as you can literally go and spend loads of hours on manuvures if needed