Help w Tshirt Design

I’ve been looking into starting my own T-shirt company w all types of different designs…having a sort of punky/tattoo theme cartoons etc. Is there anything any1 can suggest to me about getting started…Ive been told to use illustrator as for the designs on the Ts and stuff…is this true?..

You can use illustrator, or you can just color seperate photoshop into different layers. I’m assuming your going to be doing silkscreening so you can just use black and white layers and make films to burn your silk screens.