A smock or old shirt. Sure, even if markers and paints are washable, it’s simpler to thoroughly clean up in case you shield their outfits and skin by getting them use an previous shirt or an artwork smock. (Ensure to take a look at #ten over the list!) It’s https://artsuppliesonline.us/products/speedball-screen-printing-craft-vinyl-kit-print-custom-t-shirts