Free Template Plain Pleated Leather Clutch by Makesupply Leather.
Suggestions for choosing leather
This template set can be used with different skin weights. I would suggest a range of 3.5 to 5 ounces (1.5 - 2mm).
The kit does not include a template for a clutch strap. The clutch is designed for a belt width of 3/8″ (0.9525 cm). You can change this to suit your needs. The brown clutches have a ~26" (66cm) strap, while the vegetal brown clutch in the video has a ~30" (76cm) strap. I think 30″ is the best number. It wraps around the clutch housing twice and ends at the front as shown in the demo photos.