In a sauce pan, bring water to a boil. (See Note Below)

While waiting for the water to come to a boil, place flour, salt and alum into a bowl and mix to combine. Set aside.

When water boils, remove from the heat and stir in the oil and then the flour mixture. Stir to combine.

When dough is cool enough to touch, place dough onto a lightly floured counter top and knead to a soft dough. Add flour, if needed. (if it is too dry, knead in a bit of water at a time)

Divide dough into two equal parts (for two colors) and add your choice of food colors to each. Mix colors to make other colors, as desired.

Knead the food color in until it is smooth and the color has been evenly distributed.

NOTE: if making only one play dough color, you can add the color to the boiling water before you add the flour mixture.

Store in an airtight container for up to four weeks.