This is an excerpt from So-Cal Themed Wardrobe, to see the full set of videos to create the outfit seen, click here: https://www.sewingwithcinnamon.com/so-cal-style-guide
You can find the screen printing products on the Chalk Couture website, click "Shop" - transfers - cut apart designs, to find the smaller ones that work for doll tees. Be sure to purchase "inks" (not paste). The inks are for fabric. It looks like they just launched their spring summer collection today! Lots of new items to look at! https://www.chalkcouture.com/nicolefahsholtz/products/1010
You can also find similar screen printing stencils on Amazon too!