To help you get through the summer safely, here are a few tips to protect you from the sun:

Avoid direct sunlight during midday. UV radiation is strongest between 11:00 and 15:00.
Protect yourself with a sunshade, hat and clothing. 
Wear sunglasses with UV-protective lenses.
Use a sunscreen with UV-A and UV-B protection and a high sun protection factor (SPF) and apply it 20 minutes before going outside.
Use the morning and afternoon hours for exercise, walking, gardening and anything outdoors.
Drink enough water throughout the day.

Caught too much sun?
What are the symptoms of sunstroke or heat exhaustion?

Headache or dizziness, sometimes nausea
Hot head, but the body feels normal.
What should I do if I have sunstroke?

Go to a shady or cool place and rest.
Put a cooling cloth on your forehead
Drink plenty of fluids, but not ice cold drinks.