Originally Posted by Saddlebag
Try cutting into a side of leather, lol. Actually when my instructor asked me if I was nervous about cutting a pattern in leather, he seemed disappointed when I told him I'd cut out fabric that was worth a lot more. I think he was hoping I'd become a nervous wreck.
Buy a bolt of really cheap fabric. Some Walmarts still sell fabrice for $1-2/yard. You can cut and make a mockup of your project with it, and make any corrections, and then use THAT as your pattern for your leather.