Everyting about English lies in the way you sit and hold the reins. Some instructors will say that if you are sitting on the saddle in the correct postion and if you were to take the horse and saddle away then you would be left standing up ( be it a little high off the ground)'
I do suggest you obtain a copy of the BHS Manual of Equitation isbn 0-872119-33-6 - everything you need to know at the beginning is described along with diagrams. Amazon
will be able to get it.
When you've read a bit then get a training video.