In one sentence, describe what the following article is about:

Jellyfish and stray jellyfish tentacles can be very hard to see, and can remain venomous for a long time, even when washed ashore. By wearing rubber-soled shoes when you walk on the beach, you will avoid accidentally stepping on them with your bare skin and getting stung. Some evidence shows that protective lotions such as Safe Sea may protect against jellyfish stings. Applying one of these lotions before you go in the water can be a good additional precaution. Look for protective lotions at pharmacies, and shops that sell diving and beach gear. If you will be spending a lot of time in the water, or in deep waters, consider wearing more extensive coverage. The thick material of a wetsuit, and the fact that it will cover a large amount of your skin, makes it an effective deterrent to jellyfish stings. Clothing coated in petroleum jelly or similar substances is not a reliable protection against jellyfish stings. Some stores that sell diving equipment also carry special "stinger suits" that you can wear to prevent being stung by a jellyfish. Even if you wear a wetsuit, you should still practice caution and avoid jellyfish, as stings through wetsuits have been reported.
Wear shoes when walking on the beach. Wear protective lotions. Wear a wetsuit.