Things such as straighteners and blow dryers dry out our hair and the cold will dry out our hair even more. (Which is not great) Dryness will then lead to breakage in your hair
This should be at least once a week. It helps to keep hair moisturised and does not put your hair at risk of being dry. Also moisturising your hair with oils too helps. My favourite is Castor Oil. Remember to also wear a satin scarf or bonnet as it helps to retain moisture.
Examples are braids, cornrows, wigs etc. This keeps your protected from harsh weather conditions.