T-shirt Screen Printing Professionally is easy to do at home if you have the money, good tools, etc. First off, you need to get a decent printer that is more rated on the photo printing side to get a clean result. You will want to use transfer paper and make sure your diagram is horizontally so the words and drawings are going from right to left. Then you use a decently hot iron, and press the transfer onto the shirt, applying the image on. The nicer the outcome, the more expensive the tools and equipment are going to be. Hope this good for you.