Leather Wallet
You can have this acrylic pattern from here:
http://www.leathercraftpattern.com/Acrylic-template/acrylic-long-wallet-pattern-A-102
The finished size is: 7.7" x 3.5" x 0.8" (19.5cm x 9cm x 2cm).
Advice:
Leather: 2.0mm (5oz) leather for surface, size 20cm x 20cm. 1.0mm (2.5oz) leather for lining, size 20cm x 51cm.
Hardware: 201 snap x2.
Tools: If you are a new leather player, try to considerate to have tool kit here: http://www.leathercraftpattern.com/leather-tools-leathercraft-tools/leather-tool-kit/leathercraft-tools-leather-craft-patterns-leather-art-leather-carving-tool