Squish it

Decide on your first color, which needs to be light and bright. I decided to use 1 Tsp soft orange powdered dye. Mix in about a cup or two of warm water until the dye dissolves.

Dump in the second color at one end. It will naturally flow toward the other end, in a way that looks nice. 8oz of water seems to be a good amount of liquid to use for the second color. Too much water might dilute the color or overtake the whole design.

Place the shirt into the bin of dye and swish it around until it’s fully saturated in color. Then scrunch it loosely. This will make it so that there’s no white left on the shirt.

Use a gloved hand to squish, wiggle and generally mess with the shirt. It's fun. It mixes the color a little so the gradient is smooth. There will still be subtle details even if you mess with it.

It's annoying to mix liquid dye and then funnel it into squirt bottles, which is why I usually just ice dye. But for this, you can just mix a second color in a wide mouth jar and stir it. No need for a squirt bottle transfer. 1/2tsp of fuchsia for the dark bottom color.

Since the water was warm, I didn't wait the whole 24 hours for the color to batch. I guessed that it would be ok after 12 hours since the heat sped up the reaction of the dye bonding. Reds/oranges react faster than other colors, too. This shirt is very bright and makes me happy to look at.