an embroidery hoop

a few feet of relatively fine mesh material

an old credit card, library card, ID card, etc.

screen printing ink (Specific inks are sold for printing to fabric and paper; although they are kinda-sorta interchangeable, it’s worthwhile to get the right kind for the job you’re doing, especially if you’re printing to fabric and intend your design to withstand washings.)

(optional) acrylic extender base (You can mix this with ink in order to increase transparency; it also makes the ink flow a little easier.)