If you're someone who enjoys 70s disco curls one day and pin-straight locks the next, human-blend extensions are the way to go. They can be heat styled into the shape of your choice and blend easily with your natural hair. Human-blend extensions are susceptible to the elements and can become frizzy or dry, particularly on annoying rainy days. The ends are typically the first to part ways, losing their sleekness to take on a frayed finish. Nourish and lock in a straight style on your human-blend extensions, and stay one step ahead of mother nature while you're at it.

Step 1

Wet the extensions and work an oil-based shampoo through the strands from roots to tips. Rinse the hair completely. Moisturized hair retains a sleek look for longer. Oils deeply penetrate the hair to keep it healthy from the inside out. Never use a deep-cleansing or volumizing shampoo on extensions as this will dry them out.

Step 2

Coat the extensions in a keratin-based deep conditioner. Allow it to sit on the hair for 10 minutes and rinse well. Keratin strengthens the hair and helps it to retain a smooth style for longer.

Step 3

Allow your extensions to air-dry until 90-percent dry. Blow-drying removes moisture and can lead to frizz in human hair.

Step 4

Pour straightening balm and hair oil into the palm of your hand, and rub your hands together to blend them. A quarter-size amount of balm and a dime-sizeamount of oil is suitable for shoulder-length extensions; use more if your length requires it. The balm will add hold, while the oil creates a protective barrier against frizz and humidity while adding shine.

Step 5

Pull the mixture through the extensions starting 1-inch away from the roots, working the product through to the ends. Insert a wide-tooth comb at the scalp and comb the hair to evenly distribute the product. Allow the hair to finish air-drying.

Step 6

Turn on a ceramic flat iron, and allow it to heat up to the medium-heat setting. Human extensions can be heat styled, but high heat should be avoided in order to prevent split ends.

Step 7

Hold the extensions straight out in front of you. Grasp them at the roots with the flat iron and slowly pull the plates through your hair, moving them straight down without bending them until the ends pass through the iron. Bends will create creases and encourage the hair to lay in a flipped style at the ends. Repeat until the hair reaches the desired style. Coarse hair will require three to four swipes of the iron.

Step 8

Pour a dime-size amount of hair oil into the palm of your hand and pull it through the bottom 2 inches of the extension. This will serve as a final seal for the shape.