Hi Stefano,
Most people learn first gear power wheelies, easy enough to do, just pull away and wind the power on, keys is be smooth, dont give it a handful cos you will be seeing your arse go down the road (and youve done that already Milleboy ) .
I prefer second gear clutch up wheelies. Cruise to around 30mph in second then slip the clutch slightly, blip the throttle and let the clutch out. Takes a bit of practice to get it all to work together, but i found this works for me.
After that i gets a lot easier, you then can change into third and fourth.
Anyway that just my own personal experience, im sure that loads of people on here have different techniques.
Cheers,
Ritch