Once on a desert island, a person finds himself in a situation that requires maximum mobilization of physical and moral forces. The first thing to do is get over the panic attack. Panic is a natural reaction to extreme conditions, however, you need to remain calm and cool at least in order to prevent dehydration of the body, because, as you know, sweating increases in a state of stress, and fluid leaves the body at an accelerated rate. Just about finding a source of fresh water is worth thinking about secondarily. The best solution to this problem may be the discovery of a spring or fresh water. In extreme cases, you can build a semblance of a desalination plant. By heating salt water and collecting condensate, a small amount of fresh water can be obtained that is suitable for drinking. But in order to heat the water, We need to find a way to start a fire. It’s good if matches or a lighter are at hand, otherwise you will have to make fire by referring to the experience of our ancestors – using the force of friction.
Fire and water are essentials on a deserted island. Without water, a person can live only a few days, while without food – more than a month. Fire, among other things, serves to heat and scare away wild animals. After the issue of water and fire is resolved, it is necessary to find or build a shelter in which to hide from bad weather and predatory animals. The best shelter can be considered natural depressions in the rocks, if any. Such caves reliably protect both from the revelry of the elements, and from the prospect of becoming a victim of wild animals – the inhabitants of the island.
The next stage of life in the new conditions should be the search for food. You can engage in gathering: eat fruits, berries and plants, or you can make devices for hunting and fishing. Animal protein is necessary for the body, especially in such harsh conditions.
When the "life" is more or less established, it makes sense to take care of finding ways to leave the island. It all depends on what means a person has on a desert island. However, every potential opportunity to return to the mainland must be used, whether it be lighting signal fires to attract the attention of passing or flying ships, or constructing a floating craft to leave the island on their own.