Using this product is super easy. First, take the two gel colors and mix them well. Once mixed, carefully pour the mixture into the tail mold. Then, just wait for 30 minutes for the tail to set. When it's ready, put the tails on your L.O.L. Surprise Tots and dip them in cold water to see the color change. As for precautions, keep the gel away from eyes and mouth. If it gets on skin, wash it off with water. For maintenance, store the unused gel in a cool and dry place and keep the mold clean after each use.