Add confectioner's sugar to a bowl and stir it with a wire whisk to remove any lumps; use a sifter if you have one. Use 1 pound of sugar, or about 4 cups, to make approximately 3 cups of frosting.

Cream softened butter, shortening or equal parts of both in a mixing bowl. Beat the butter or shortening with an electric mixer at medium speed until no lumps remain. You'll need about 1 cup of fat for every pound of confectioner's sugar. You can use 1 cup of vegetable shortening, two sticks of butter or 1/2 cup of shortening and one stick of butter. Butter is often used in frosting because of its taste, while shortening is better at holding its shape when you pipe flowers and other decorations onto a cake.

Mix in clear vanilla extract, almond extract or a similar flavoring to taste, using about 1 teaspoon of flavoring per pound of confectioner's sugar. Clear vanilla extract doesn't change the frosting color as would happen with brown extracts.

Add the confectioner's sugar to the mixing bowl in small batches until all of the sugar is thoroughly incorporated with the butter or shortening. Stop the mixer each time you add sugar or the beaters will throw the powdered sugar out of the bowl.

Mix in 2 tablespoons of water for each pound of confectioner's sugar. Use the water as a substitute for milk. Or, instead of water, use orange juice, which also dissolves the sugar but adds some orange flavor to the frosting. Do not use orange juice if you want to make pure white frosting.

Mix until the liquid is thoroughly incorporated with the sugar and the mixture forms stiff peaks. The finished frosting should spread easily but hold its shape well.

Distribute the frosting to separate bowls for each color you wish to make. Add food coloring gels or powders to color the frosting. Avoid liquid food coloring because the amount of food coloring needed to achieve the desired color often makes the frosting too runny. Skip this step if you only need white frosting.