Start with your horse safely tied.
Brush your horse’s back and girth area being careful to remove any dirt or grit that may cause chaffing under the saddle or girth. Brush so all the hair lies flat. It is traditional to saddle from the near side (left side) but you should be able to saddle from the right (off side) if necessary.
Check for any sores or wounds that may cause discomfort under the saddle area. Don't place a saddle over a wound.