I wanted to share a few t-shirts designs that I've made for my client Headline Shirts. I have done many more and the process has been great. I usually work out a sketch in Photoshop. Once it is approved, I move to the final line art and colors. Once those are approved, I take the file to illustrator and I use live trace to vectorize each element. They are all in separate layers. I use live trace with "ignore white" box checked. You just have to make sure to replace any white elements with a color like cyan, and later replace cyan once the layer has been traced. This helps make vectorizing much easier. Check out the many other designs they offer at the link below. Hope you like them.