Thanks Camille! You can sort the cards within a stack. When you're in your Dashboard, click "Stacks" in the menu on the top of the site. Then pick a Stack you want to work on, and click the title of the Stack to navigate into that Stack.

From this page, you can click and drag any card to adjust the sort order where you want that card to be. Once the page refreshes, the Stack's order has been set.

Hope this helps!