Direct-to-Garment Printing (DTG) is the youngest form of printing, having been around for just over a decade. Since it is a digital printing method there are no minimums and artwork can be printed in full color.
DTG Printing uses white and CMYK inks to create the rainbow of colors, but can only print on 100% cotton products.
Artwork for Digital Printing only needs a transparent background, however the higher the resolution, the better.
The ink used in DIgital Printing has a nice, soft feel to it, and is still quite versatile. Because of this, the primary costs involved with Digital Printing come from the ink.