Dress appropriately
If you want to stay cool at work, the first thing you should look at is what you’re wearing. Thick shirts are perfect for winter, but wearing them in the scorching heat leaves hideous sweat patches. Make sure you’re dressed appropriately, otherwise you’ll be in permanent discomfort from the start of your day until the end.
Personal fans
Getting your own fan is an investment that will go a long way, particularly if your office doesn’t have air-con. Prop one up next to your office computer, and the only time you’ll need to worry about the heat is whenever you get up from your desk.
Drink lots of water
This may sound obvious, but a lot of office workers tend to 
forget that being sat at your desk for most of the day doesn’t mean you’re not quickly dehydrating. Try putting a water bottle in the freezer overnight, meaning that the next day you’ll have a constant supply of ice cold water throughout the day.
Cut out the coffee
Having a hot drink at work doesn’t mean that your body will start to feel hotter, but the caffeine in tea and coffee can increase heart rate and subsequently blood flow, causing your temperature to rise.
Avoid a big lunch
Small meals are a must if you don’t want to become too overheated and sluggish at work. Eating big portions means that your metabolism must work harder to digest it, which increases your bodies’ temperature.
Keep windows closed
Naturally, you’ll be inclined to think that opening a window lets in a breeze and therefore cancels out the hot air in your office. In fact, the complete opposite is true, as having windows open replaces the cold air you built up in your office with the outdoor heat.
Avoid your lunchtime walk
When sat at your desk all day, there’s nothing you want more than to get outside on your lunchbreak and go for a stroll. Of course, in sweltering heat it only takes a quick walk around the office block to leave you dripping in sweat, so as painful as it may feel, your best bet is to stay inside so you’re close to the cooler air.
Water on your wrists
You might look slightly bizarre going to the bathroom and running your wrists under the tap, but this cools the main veins that run through them and will lower the temperature of your blood flow.
Avoid electronic devices
Phones, computers, tablets; electronic devices are crucial to the day-to-day working of office life, but they also give off a lot of heat. It’s impossible to avoid using them whilst at work, but limiting your usage wherever possible can keep you that extra bit cooler.