DIY galaxy shirt- splash/spray with bleach, tie-dye red, bleach again, paint/sponge on red/blue dye/paint and finish with white fabric paint stars flicked on. would also be a nice technique for a table cloth or throw pillows.
DIY tank top - item: scissors, bleach, plain tank top/t-shirt. Dip dye the bottom of the shirt with bleach. Wash it out and let it dry completely. Then cut the part you bleached into thin strips and tie a knot at the ends.