In one sentence, describe what the following article is about:

If you haven’t had a haircut in a few months, you probably have split ends. This is normal. However, split ends can cause a lot of frizz. Get your hair trimmed every six to eight weeks to avoid splitting and breakage. Book your appointments well in advance so that you won’t forget. Cotton bed linens create friction during the night as you toss and turn. This friction causes frizz, along with tangles, breakage and split ends. Satin has a much smoother texture, so sleeping on a satin pillowcase will reduce the friction that causes frizz. Satin also helps hair maintain moisture, which helps combats frizz.  Cotton and other fabrics tend to dry the hair out. Wrapping your hair in a satin or silk scarf before you go to sleep will provide the same benefits as the satin pillowcase. Tousling and running your fingers through your hair causes frizz because it disrupts the smoothness of the hair shaft. The more often you touch your hair throughout the day, the frizzier it will become. Whenever possible, avoid touching your wavy hair to maintain your smooth style. Natural oils from your scalp smooth and moisturize your hair, which prevents frizz. Shampooing frequently strips your hair of those natural oils. Whenever possible, wait at least two days between shampoos. This will give your scalp time to create more natural oil. Four shampoos every week should be enough. On the days when you don’t shampoo, rinse it and then apply conditioner as you normally would. You can also use dry shampoo in between regular washes.  If you have fine hair, you probably need to shampoo every other day. If you have very thick hair, you can probably go three of four days without shampooing. Wavy hair tends to get dehydrated fast, which makes it prone to frizz. A weekly deep-conditioning mask can help to rehydrate your dry strands by delivering a large dose of much-needed moisture. These masks will also keep hair feeling soft and restore damaged hair cuticles. Look for deep-conditioning mask products that contain glycerin, proteins, shea butter and other hydrating ingredients to prevent frizz.

Summary:
Get regular haircuts. Sleep on a satin pillowcase. Avoid touching your hair during the day. Reduce hair washings. Use a deep-conditioning mask once per week.