And resist that nightcap. Alcohol may help you fall asleep more quickly, but it’s bad news for the quality of your sleep, with REM sleep (vital for learning and memory) the worst affected. It’s also a diuretic, meaning you’re more likely to wake in the night needing the toilet if you booze before bed. Avoid.
An enjoyable bedtime routine can relax you both mentally and physically. With repetition, your body and brain will come to recognise its steps as a sign that it’s time to sleep. Your ritual could involve taking a warm bath or shower, meditating, talking to your partner or family, writing a diary, reading a book or listening to music with the lights turned low.
So what kind of music is best for sleep? In 2015 the composer Max Richter set out to answer that question by writing an eight-hour piece designed to accompany a good night's kip. He consulted a neuroscientist about sleep phases and how the senses operate within them, and learned about the types of sonic backgrounds that are appropriate for each stage of the sleep cycle.
The resulting piece, "Sleep" (which premiered on BBC Radio 3) makes extensive use of repetitive sonic patterns and low frequencies, both of which are thought to induce the deep, "slow wave" sleep vital for consolidating short-term memories and for structuring information within the brain.
Whatever sort of music you choose, it's crucial that it should be relaxing. If you feel that listening to death metal helps you to relax, then by all means incorporate a listening session into your bedtime ritual.