If your skin is sensitive and burns easily, or has a tendency to burn-use a Sun Protection Factor greater than 15. If your skin is tans easily , but sometimes burns-use a Sun Protection Factor of greater than 10. If your skin tans easily - use a SPF of greater than 8. You can always use a lower factor when you've developed a tan, say after one week. Remember to reapply at least every 2 hours as sweat, water and towel friction will wear it away.
Most skin cancers are completely curable, especially if detected in the early stages.
Some types of skin cancer are associated with continued exposure to the sun over a long period. People who work outdoors all the time are more at risk here. Malignant Melanoma , the most dangerous form of skin cancer, can be caused when skin that isn't used to the sun is exposed to frequent bouts of strong sunlight. It can show itself by the change in the look of a skin mole. Any new, growing, or changing mole should be shown to your doctor immediately.