The holster was really a piece of cake to do. The gusset is made from a double layer of sole leather. It is tapered slightly and inch or two forward of the trigger guard to the end of the holster. The sole leather was cut on my scroll saw.
I marked out where I wanted to stitch, and then used a hand crank drill with a straight double fluted bit to make the holes on one side of the holster. I folded the holster over and transferred the locations of the holes to the other side of the holster, and drilled those holes. I checked to keep things lined up as I went along.
The belt loop was then sewn on the back side of the holster. That was the most difficult part.
I marked along the sides of the gusset the center where I wanted the stitching to be. I used barge cement and glued in the gusset. I very carefully drilled the holes throught the gusset, using the predrilled holes on the outer edge of the holster as a guide, and exiting on the drawn center line of the gusset so they would line up with the edge of the holster after it was folded over the gusset. Glued and clamped. I took a couple of locating stitches along the edge just to help keeping things in line as I stitched it together.
The edge was trimmed and finished off with a one inch belt sander. The holster was dampened to shrink fit it around the pistol. The pistol was oiled and wrapped in several plastic bags, the type the morning newspaper is delivered in. The color was done with Kiwi Cordovan, Meltonian Tan, and plain old cheap red wine. Oiled and buffed.