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Although a breeze may feel comfortable coming from outside, an open window will let warm air into the building. By keeping the windows shut and closing the shade, you block the hot air and direct sunlight from coming inside. Use a sun lamp, or light therapy lamp, to replace natural without a majority of the warming effects. These can be purchased online. Electronics generate heat, especially if they are battery operated. Keep your personal devices in bags, cases, or on your desktop so they are not in direct contact with your body. Use external keyboards if you work on laptops to avoid overheating components right underneath your hands. Small fans can help reduce heat while sitting at your desk. Place them next to your computer or under your desk to keep your feet cool. Personal fans can be purchased online or many big-box retailers. Personal fans range from basic AC adapters to USB-powered. Find one that fits best in your workspace. A spritzer with aloe or peppermint is a quick and easy way to cool yourself down in a pinch. Many of these sprays can be purchased online or even made at home with water and essential oils. Make your own spray by filling a spritzer bottle with distilled water and adding 8 to 10 drops of peppermint essential oil.

Summary:
Shut the windows and close the blinds. Keep electronic devices away from your body. Purchase a small personal fan. Use a cooling spray.