Free pattern Backpack/drawstring bag from Creative awl.
You can make 2 sizes:
big size: 40.5 x 25.5 cm | 15.9" x 10"
small size: 32.5 x 21 cm | 12.8" x 8.3"
You will need 3-4 oz soft or at least medium soft leathers. Made out of vegetable tanned Waxy leathers from Badalassi Carlo.