Start here!
 But before the start box in cross-country learn the German classical dressage basics which include riding from your seat, legs and half-halt. 
Back that up with natural horsemanship with safety as a priority.
My purpose in teaching is not to take my students to the Olympics, but for us to stay safe, learn something and have fun.  I try to end my lessons with summing up the positive points so they remember them and most times my students walk away with some real self esteem and a smile on their face and its really worth it.