We do a lot of blind Patches, in fact WAVE had a new one on her starboard chine. It survived intact while the rest of the chine around rest was bashed to slivereens.
Trimmed the strings and removed the paint sticks, sometimes bits get left behind in the epoxy. Those will get sanded off.
WAVE was moved outside on the finishing dolly for sanding with 60 grit on our random orbital sander, we used the French doors today.
Sanded the repair areas to get them flush. While I was sanding I found an area that I missed, so I made another blind hole patch for that.
WAVE is all different colors, which makes it harder to see areas that need to be faired, so we put on a "Show Coat" of primer, to show us where the hills and valleys are. We used TotalBoat Topside Primer applied with a Mighty Mini roller cover, all available from Jamestown Distributors.