I apply designs to tshirts all the time with Avery printable screenprinting labels... You can get them at Office Depot. You might be able scan the design on your scanner and then print it on the transfer... Not sure how clear the design will be, but if you have Photoshop, it might be workable.

Otherwise, I don't know of a way to do that without sewing it.

[color:"Red"]
You tell me that I sin.
You say I'm bound for hell.
So once your judgment condemns you
I SHALL SEE YOU THERE.