Go to the Vulpine:Be a Fox With a Sword! Page, and click the Manage Your Pledge/Back This Project button.
Increase your pledge in the pledge amount box to reflect the amount of extra copies you wish to add. ($15 per Copy, or $25 per Early Access copy)
Do not change the tier you have already pledged at. If you wish to change tiers while still adding additional copies, you will need to switch tiers, and then increase that tier’s pledge to reflect the amount of extra copies you wish to add.
After that, you’re done! We’ll be sending out a survey after the Kickstarter Campaign that will ask you about your add-ons.