Coloring your own hair at home can save you a great deal of money while giving you more control over the results. If you have used the same hair color for years you already know that you are not allergic, but if you are dyeing your hair for the first time it is important to do an allergy patch test. It is always possible that you will be allergic; if you do have a reaction you will need to choose a different brand of hair color.

Open the box of hair color and look at the instructions. Using the instructions mix up a small amount of hair dye and developing solution.

Place the cap back on both bottles, making sure the seal is tight. If the bottle is left open the hair dye and developer will not work properly.

Dip a cotton swab into the solution you mixed. Apply the mixture to the inside of one elbow. Leave the solution on your skin for a full 48 hours.

Watch for signs of an allergic reaction, such as redness, itching or swelling. If you notice any of these problems wash the solution off at once and call the manufacturer of the hair dye. Most manufacturers will allow customers to return open boxes of hair dye if they experience an allergic reaction.