Staying cool for me lately is taking Cold showers which in turn helps me maintain temperature. Sure I can use fans around the house but for the most part it doesn't help my body much and its not fun watching a movie while the fan is blasting at the same time. Cold showers are my best friend and i'm talking like deep cold. Some people are more naturally cold so heat does get to them but they have a faster rate of dying down after a while, like my girl, she's cold very easily so I tend to be the heat rock. Those who can be colder can maintain a good amount of heat, i'm the exact opposite, I need cold just to maintain body heat.
Cold Showers can help not only maintain the body's temperature but can also aid in improving skin tone, weight loss, fat loss and open up hormones to the sexual organs. This in turn can lead to irony where because I need cold water to maintain my body heat in hot climate, my body burns calories just to stay warm. Believe me, they never get easier but they can be interesting if you do practically nothing but cold showers and only warm water a few times just to clean yourself has many benefits. In the winter it helps build a tolerance for cold weather so as long as its not so cold that your spit freezes in mid air you should be fine. The body has to burn off twice as many calories just so you can stay warm so look at the benefit from that. Make it a habit and get that amazing feeling on your skin and as much as you may not believe, cold showers do increase testosterone (it'll hit you once the body is at the best temperature of warmth).