We should wear cotton clothes and light coloured clothes in summers. Cotton is a good absorber of water. Since we sweat a lot in summers, cotton clothes absorb sweat from our body and exposes the sweat to the atmosphere, making its evaporation faster. During this evaporation, particles on the surface of the sweat gain energy from our body surface, making the body cool. Further light coloured clothes are poorer absorber of heat and would be better for summer.