In a small bowl or medium cup, combine the water, gel food coloring, and oil. Mix well
Add the colored water to the dough and stir until it begins to form a ball of dough. Turn out the dough with all the remaining flour onto a clean hard surface. Knead well until smooth.
If the dough starts to get a little dry, rub a little bit of oil on it with your fingers and knead it again. Store in an airtight container, wrapped in plastic wrap, or in a ziplock bag with all the air removed.
This playdough is only good for two or three days at most.