Start by learning yourself!!
As a beginning driver of a very well trained mini, I can only thank his previous owners for all the work they put into his training. I was lucky enough to take lessons from a great trainer , and learnt alot. I had read everything that I could get my hands on first, and plan to train my next mini myself, but I know that the steps are not easy.
1) find a good fitting harness-
2) find a sursingle and bitting rig
3) find -or make shafts that can take abuse while ground driving
4) find a trainer to help me -already done that one
5) have lots of time and patience-got that too
6) ask for help from people more intelligent and experienced than me!!-SHOULD HAVE PUT THAT FIRST
Have fun and don't forget to check out the videos on youtube.. lol... they are hilarious...