There are a lot of great ideas for sling pouches on the main site, and many of them suggest leather for their construction. I know from my personal experience in creating leather things that the idea of doing a new project on leather can be daunting. If leather is expensive in your area then you don't want to ruin it. One thing I like to do either as a mock-up of leather, or as an alternative is to use Duct Tape Fabric. You can make a patch big enough to fit the template for the sling pouch you want, and cut it out. It's not sticky, and is very durable. Give it a try.
Here's how to make it, instructions under the photo.
SupStep 1: Make a duct tape swatch of "fabric" that is seven inches long by four strips wide. To do this, simply:
1. Lay a strip of duct tape sticky side up on your work surface and place a second strip sticky side up so it slightly overlaps the edge of the first strip. Repeat until you have four strips of duct tape overlapping
2. Turn the sheet so the sticky-side-up strips run vertically and lay a strip sticky side down over the sheet. Repeat with additional strips of duct tape until the sticky sides are covered. Don't forget to overlap the edges.
3. Trim off edges.
Note: Duct tape fabric can be made to any size. For illustration purposes, we showed a small piece of duct tape fabric under contruction. Remember that you should try to keep the size of your fabric manageable, as working with longer strips of tape can get "sticky", and you can always tape sections of fabric together to get a large sheet.