Many Britons underestimate the strength of the British sun, especially when they're at a festival.
About 2,000 people die from malignant melanoma every year in the UK, and the number of cases is rising.
At a music festival you can spend several hours in the sun, so protecting yourself from the sun's harmful rays is vital.
Wearing a wide-brimmed hat, regularly applying suncream of at least factor 15 and using an after-sun lotion will ensure that your festival experience isn't ruined by sunburn, dehydration or worse. Find out how to apply sunscreen properly.
Clive James of St John Ambulance, which provides medical assistance at many festivals, including V Festival and the Notting Hill Carnival, explains how to deal with the effects of the sun.
Sunburn is skin damage caused by ultraviolet (UV) rays in sunlight. Your skin overheats and becomes red and painful and may later peel or blister.
"Cool the skin down by dabbing it with a cool, wet towel or tissue," says James. "If the burn is really bad, have a quick cold shower."
Don't go back into the sun until the sunburn has healed. Drink plenty of fluids in order to cool down and replace the water lost through sweating in the sun.
Apply calamine or after-sun lotion. For adults, painkillers such as paracetamol or ibuprofen can relieve pain and reduce swelling.
Dehydration occurs when the normal water content of your body is reduced. If you are thirsty, you're already likely to be suffering from the effects of dehydration.
The signs of dehydration include a dry mouth, lips and eyes, clammy hands and feet, headaches, lightheadedness, and concentrated, dark urine with a strong odour.
"Drink plenty of fluids," says James. "Isotonic drinks are good as they help replace lost minerals as well as sugar and water."
A sweet drink, such as cola, can be useful for replacing lost sugar, but lots of water is the best way to rehydrate. A salty snack, such as a packet of crisps, can help replace lost salt.
Heat exhaustion occurs when the body can't control its temperature due to overheating.
Symptoms include headaches, dizziness, nausea and vomiting, muscle weakness or cramps, tiredness and high temperature.
"Move to a cool area and drink plenty of fluids," says Clive. "We know that ecstasy can be a cause of heat exhaustion at festivals."
Remove any excess clothing. To cool your skin, shower or sponge yourself using lukewarm water.
If it's not treated, heat exhaustion can develop into heatstroke, which can occur suddenly and with little warning.
In addition to the symptoms of heat exhaustion, other signs of heatstroke include confusion, hallucinations, unconsciousness, palpitations, flushes, and hot and dry skin.
"The person needs to get their body temperature down as quickly as possible," says James. "Give them water to drink and cover them with a damp towel or sheet."
Contact first aiders at the festival, as the person with heatstroke may need to go to hospital where they can be given intravenous fluids through a drip, and medication to lower their body temperature.
Article provided by NHS Choices