The cards below have been put into a certain order using a particular rule. This order can be written as AC2HJS7SKD3D. Keep in mind that it's entirely possible to come up with more than one set of rules that the order could conform to. For this puzzle there's only one right answer, so if you come up with an answer and it doesn't work, try coming up with a different ordering rule.
The following cards have not yet been ordered. Arrange them using the previously mentioned rule and write down the order as noted above. That sequence can be used as a 15% discount code. Good luck!