Drinking lots and lots of water and othe fluid like glucose water or lime water helps alot in staying hydrated and reduce the chances of sun stroke.If you are working in ac office then do not go out directly from ac in the hot afternoon.Make sure you sit for someimes in normal temarature before going out.Sudden change in outer temparature is not good for our body.If you are riding 2 wheeler, wear cap sun glasses and apple some lotion as well.Make sure we do not forget birds and other animals facing this summer heat and always try your best to arrange water for them as well.