one tip I can give you, if you are over the age of 21 or have driven a car for 5 years or more, do your CBT on a 125cc nothing more nothing less, that way as soon as your pass your CBT you can get your licence and jump on anything up to a 400 as soon as you pass instead of hacing to drive a 125cc for 2 years then going up to 500 and below then moving higher.
All you have to remember is that if you have never ridden a bike before, take it easy on the clutch, you release it to quick and you have the slightest bit of power you will more likely get the front end way off the ground
just take your time. Are you using their bike or your own?