I used a 1-1.5mm thick veg-tan leather.

You will need a piece about 3 ½" x 3 ½" for this project.

Once you have all your pieces cut out, give them a couple coats of leather oil.

Now color your leather with dye, paint, or engraving as you choose. 

I went with a pro dye medium brown in a airbrush.

Let dry.

Next take a extra small sam brown (Tandy Leather), and then add your belt loop section and your strap to the back and stitch across.

Note: place your securing strap to the far left edge if you are doing a right handed holster.

Now just fold your holster like a taco and line up the stitch holes. Using a saddle stitch, start at the top and work your way down. 

Add your gun keychain and display!