Most of us have a misconception that we lose more hair in winter than in summer; however far to the contrary most of lose more hair in summer due to the hot summer air that causes not only damage to the scalp, but also to the hair. Summer hair carecan prove to be very important considering the loss of hair due to the ultra-violet rays of the sum that are harmful to hair health and cause graying of hair and dry and brittle hair.
Summer hair health care involves following certain tips like:
The first step lies in blocking the ultra-violet rays from causing damage to hair; this involves wearing caps, hats and scarves that are used loosely to not restrict the supply of blood in the scalp. I would strongly advise other methods like the use of benzophenones or cinnamates that act as a SPF for your hair. As an alternative it would be great to leave a conditioner and sunscreen on the hair before leaving for outdoors to prevent damage caused due to ultra-violet rays, however I would say that our hair should be washed well after returning back home.
Swimming and enjoying ourselves in the beach has always been most loved activities during summer to keep cool; however chlorine present in pool water and salt present in sea water could dry the hair and cause split ends. It has been observed that dry hair is more prone to hair damage than wet hair; dry hair soaks in most chemical in the water faster. Soaking the hair in non chlorinated water before going for a swim or bath in the beach helps when complemented with washing it soon after with a clarifying shampoo to  wash off chlorine and salt residues.
I have heard many of my hair beauty conscious friends reveal their hair care secret; they say that they never use hair care techniques that direct heat towards the hair during the summer. The use of most favorite beauty tools like hair dryers and curling hair directly on the hair causes irreparable damage to the hair and had the same effect as the UV rays of the sun. Beauty tools that blow hot air have the effect of damaging the cuticles of the hair and dry them up, making them susceptible to split ends and breakages especially in summer. I would say that it is always best to not hot air dry hair before styling but instead air dry it to provide protection the follicles.       
The same principle applies to taking a hair bath with hot water during summer; hot water dries hair and increases fall of hair. Some beauty conscious family members have always advised me to shampoo my hair only a few times in a week and to use a good conditioner. The use of beautyhair products that contain the silicone ingredient dimethicone proves useful; to protect the hair cuticle and lock in moisture in the hair. The use of a deep conditioner with protein or keratin could give additional protection and overcome frizziness.
Water is the elixir of not only body health, but also hair health. The hair fall and dryness remedy that complements most other remedies is drinking a lot of water; enough to keep hair flowing healthy and shiny. I would lastly surely recommend trimming of the hair to avoid static and frizz hair and saying "No" to salon treatments like bleaches and dyes in the summer months.