IF you are a diy enthusiast, you will probably want to craft any product you need on your own even if they are low cost products and are not worth putting so much effort in it. A baking tin is a simpel product which you can purchase for low prices. However you may still want to craft it by a diy project.
If you want to recycle unused tins to craft a useful baking tin, you will need a tool to cut tins appropriately and join pieces together to form the baking tin. IF you are not sure about what to do, you will need to watch some diy tutorials. But still it is a simple project.