for good looking custom T shirts you can make yourself, most office supply stores sell iron-on printer media.

1) You create a graphic of whatever you want...
2) if there is text, you have to flip it into a mirror image
3) put iron-on media in printer and print your graphic
4) iron it onto the T shirt

Its not quite as durable as a commercially sold product that uses rubbery ink that stretches with the fabric. But for special use (parties etc) it's a fairly inexpensive way to make custom "shirts with a message", and you have total control of the content.

https://www.dropbox.com/sh/ey71h8ep047758h/AAC12jNM0Hz9Q8zsh5iDeqNHa?dl=0