Put the saddle on the horse without the pad on and see how it fits. Put it up much farther on the neck than you are used to, and slide it back (it lays down the hair). The saddle will slide right where it should go-- you'll be able to feel it when it stops where it should be.
When the saddle is in place, take note of where it sits, even loosely secure the girth if you need to, and that is where it should be when you use the pad. You can also do the same thing with the pad to get it situated.
Anyways, without the pad, slide your hand under the skirt, it should fit and not be bridging--- not touching the horses back in the center under where you sit. The saddle should not touch the withers or sit over the shoulders. You should be able to look down the gullet/channel and see daylight in the channel only, not open air past the spine. The saddle also shouldn't be sitting directly on the spine.
If anything is off from what I've told you... well I've told you the basics and without those, the other smaller things won't make a difference.
Owner and head trainer of SE-Wisconsin Horse Care
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