It could be done in a number of ways. Some tie dying actually isn't done with the dip & dye method anymore. You can take plain spray bottles and spray the fabric dyes on shirts to to get a tie dye effect.
This shirt could have used fabric
paints instead of dyes. Paints do not bleed as much, so they are more controlable. They laid down a paper pattern of a cross on a shirt. Then sprayed tie dye around the paper pattern. Since the paints don't really bleed, they didn't go underneath the pattern. The pattern is lifted away and it's a clean area underneath.
A second technique that could have been used is painting the cross with a fabric
resist. A resist creates a physical barrier. Wherever the resist is applied, dyes & paints won't seep through that part of the fabric. If it's a washable resist, then, as the fabric is washed, the resist is washed away, leaving no telltale signs of where it was.
Melted parafin wax can also be used as a resist but has to be ironed away instead of washed. This is how the East Indian batik fabrics are made. Where the wax is applied, again, no dyes penetrate. Once the dyes dry. The wax is removed by repeatedly placing on paper towels on the wax & ironing until all traces of the wax are removed.
You can get all your tie dye paints & dyes & some basic instructions from
Dharmatrading.com
My favorite tie dye paints are the
Setacolor Fabric Paints. They leave almost no feel to materials. The fluorescent & bright colors are really BRIGHT! The black is a true black. The pearlescent colors leave a nice sheen. And you can water down the colors to get nice, soft pastel or watercolor effects. They also can be used for a technique called
Sun Paintingwhich is another way to get the cross or any pattern onto the shirt.
