How to fit and iphone 4s case on a 5c?

So I had an Iphone 4/4s and I was so addicted to the cases for my phone. I had over 70 cases. I got the 5c for my birthday which means I couldn't use those other cases anymore. I have sold a few, but I really want to use them again. Is there any way that I can fit them on my 5c without buying new ones. I've seen on Youtube how to fit an Ipod case on an Iphone. But how about a 4s case on a 5c? Please tell me if there's a way to make them fit!

I don't see any way to make those cases fit they were designed for an iphone 4s and not a 5c.