There are many available materials to choose from. Some are easy to work with. Some are better in tactical situations and others are better for western style holsters. Nylon: It is cheap and easy to cut and sew. But if you want to have it hold its shape then it must be wrapped around something that can maintain a shape like plastic or a formed leather. Otherwise it is too floppy to insert and remove a weapon repetitively.
Leather: It is the most common material for making gun holsters and is easy to work with since you can purchase already tanned leather. It can be sewn, bolted, pressed, formed and fastened any number of ways. The cost is more than Nylon per yard but it holds its shape and lasts much longer through the wear and tear. For better tips click here.
Plastic: It is not really an option unless you have the proper machines to extrude or injection mold it. The cost to go that route makes it less feasible to create different models and styles simply for your personal use.
Carbon Fiber: It is more feasible than plastic because of the recent availability of carbon fiber sheets and the resins. Kevlar is also an interchangeable fabric that can replace carbon fiber. New mold release technology has allowed the home tinkerer to experiment and create with carbon fiber and become quite good at it. Many bicycle manufacturers have been able to make their first prototypes in their garages with materials and molds that they have bought online. For home use, leather is the material of choice. It is workable, strong and resilient. Some of the great techniques that can be used to make professional gun holsters are:
Burnish Edges: To do this you need to first cut arounded edge on the leather. Then after dampening the leather edge use a burnishing tool to rub back and forth until it starts to feel sticky or does not slide back and forth as easily. This creates a smooth and hardened edge to your leather pieces.
Carving: Once a stain or oil has been applied, you can carve designs in the leather that will reveal a light color under the darker surface. This is great for creating designs in the leather.
Braiding: Braided leather can be very cool for seams. This can be done by sewing the leather with other lengths of leather rather than string or twine. Creating braided patterns in the stitching can be very cool to enhance your holster.