Keeping information on orders is always a good idea. You should have a record system set up to retain all order information such as customer name, address, shipping address and contact information. You should also be recording for future reference, information pertaining to the quantity of the order, specific shirt brand and color you used and the ink color of the order. Having all this available makes it very easy when the customer wants to reorder. Your customer may likely remember that the ink color you used was blue, but there are many shades of blue. Not to mention that each manufacturer will have their own spectrum of blue inks. Another good idea is to keep a test print of each order that you print. Not only will this be a great method to record your order details but you can use the test print to display in your shop or keep as a scrapbook.