Thanks for the tips and compliments all. This one came out pretty. I was trying for a bulls-eye but failed, and the green wasn't very green but oh well. I have one more in the dryer and one in the washer.
I redid a prior failed attempt. It still didn't turn out right, but at least now you can tell it's a tie dye. Before it looked like a white shirt with vague stains.
I get my dye prepped by adding hot water, salt, and vinegar. Wash the shirts, and fold them into the pattern I want. (It's a learning process.) And then dip or squirt the dye on the sections. Then I let it sit for 24 hours in a plastic bag, rinse, and toss it in the washer and dryer.
What type of dyes are you using? I heard foragers use friuts, (blue berries), vegetables (certain sqashes) and foragers use wild plants (poke weed).