The first thing I did was to make a very rough measurement and cut out a square of kydex to wrap around the pistol.
Then I put the kydex in the oven and heated it until it was floppy. (250 deg) I quickly removed the kydex and placed it on my foam that was on the floor. I put the pistol on th kydex, wrapped it around and put the other piece of foam on top of it. (foam is backed in wood to make it rigid) Then I stood on the whole thing until it cooled off.
I traced out the areas that I wanted to cut away, removed the pistol and and cut close to the tracings with a Dremel cut off wheel. I then used a Dremel sanding wheel to do the final material removal and shaping.
On the open ind of the holster the leather tab is sandwiched between the kydex and thick rubber washers It is screwed together with machine screws, aluminum finish washers and some fasteners that I don't know the name of. They have a threaded post coming out of a flat base. Around the edges of the base are 3 prongs that stick up. Pre drill your holes then heat up the prongs just enough so that they will stick into the kydex. Wait for it to cool and screw it together.
The closed side of the holster is a little trickier. I cut out a rectangle of kydex heated it and folded it in half. then I molded it to the holster. After cooling I trimmed it up and cleaned up the edges. I used my Dremel sanding wheel to rough up the interior of the tab where it contacts the holster. Then I roughed up the holster where it contacts the tab. I also drilled 2 holes on each "leg" of the tab also. It was all epoxyed together with Locktite plastics epoxy and allowed to set up. Then the leather tab was screwed into the tab using the same hardware.
The belt tabs are held on to the leather tabs with hex screws and those locking threaded posts. Rubber washers are sandwiched in there to give it tension.
All kydex edges were sanded with 600grit sandpaper to smooth things out.
All hardware on the back of the holster is covered in Dr. scholls moleskin for comfort.
When worn in the pants but over the shirt the whole rig practically disappears it is so comfortable. With the shirt tucked it is still very comfortable and it completely disappears visually.
Due to the rubber washers inside the holster it is adjustable for retaining tension. The gun will not move until you remove it. It is very thin, very light, very comfortable and fairly easy to make.
Like I said, if I can do it anyone can!