All of which means we can miss out on deep, restorative sleep and feel tired the next day. ‘It should only take around half an hour in the freezer for your sheets to reach a comfortable cool temperature as you want to be sure you don’t actually freeze them!’ In the same vein, Dr Browning suggests using a hot water bottle filled with crushed ice and cold water to cool you and the bedShe adds: ‘Plus you could spray yourself with cool water from a misting water bottle.’ ‘Sharing covers creates one pocket of trapped body heat, whereas separate ones let you control your own temperature.’ Dr Banerjee suggests placing a bowl of cool water in front of or underneath a fan to add moisture to the air.