I recently came across a website for making custom made attire, http://www.bonfire.com. The website provides everything you need, they do take a base cost as they provide you with all the material you need.
The first shirt I have had in mind for a long time, I just didn’t know how to design it. Its based on a baby and a daddy both drinking their own versions of their bottle. The front shows a baby with his/her bottle and a dad with a beer bottle, and says “Bottoms Up.” The back says how they both love their bottles.