Measure about 50 mL cornstarch and add to your bowl. Make sure there are no lumps.
Measure an additional 35 mL water. Add the water and 2-3 drops of food coloring slowly to the cornstarch. Mix everything in the bowl with your fingers until all the powder is wet.
Keep adding water until it feels like a liquid. Try tapping on the surface of the mixture with your finger. When it is just right it won't splash - it will feel solid.
If your slime is too powdery, add a little more water. If it is too wet add more cornstarch.
Pick up a handful of your slime and squeeze it. Then stop squeezing it and see what happens. It is VERY cool!
Do not pour wacky mud down the drain, it will clog it.