[header] How to make safe and easy play dough [title] Squirt the paint into the cornstarch. [step] Add 2 large, heaping tablespoons (18 to 20 g) of cornstarch to a medium size bowl. Squirt some tempera paint in your chosen color into the cornstarch. 
There's no exact measurement for the paint--add what looks like enough to help form a dough with the cornstarch. [substeps] Don't worry about adding too much or too little paint.