"Rattle can" it
Is it a single color? If so, I would recommend making a stencil and buying a can of spray paint. Buy a solid colored tee shirt (or 5). Get cheap ones to test with, once you get it how you like it, then go buy as nice a shirt as you want, and do it on that. You would be surprised how well a good ole rattle can will work on a tee shirt. Also, you can buy some cardboard (not corrugated) and tape it in place if it is a complicated logo (or just mask the tee shirt with tape) instead of actually making a stencil. A stencil will make repeated tests easier though.
If it's not a single color, then I apologize, because my post is wholly useless...