It is hard to say without knowing the horse. Keep in mind that SS horses are very much "go forward." Whereas with hunt/western horses you are more inclined to keep the horse slower and less reactive, many SS horses are not like that, just go with the horse and ride. Hands are up a bit higher, depending on the horse you lower leg may stay off its sides. You sit further back in the saddle, you want your bum up against the cantle for the most part-doing so allows the horse to really come up and back to you. I have only been riding SS for a year, although I have been riding for many years, so I probably am not as much help as others will be.
Are you exercising the horse at a show?