Alexander Selkirk waited on his island for over four years before he was rescued. In the meantime, he began to love the solitude and simplicity of his castaway lifestyle, and is later quoted as saying "Nowhere could I be as happy again as I was on my island."
In the meantime, he collected sea salt from hollow rocks, and found fruits and vegetables to supplement his regular diet of goat meat. He also killed the occasional sea lion, using their oil for lighting at night. He sewed himself new clothes from goatskins, using strands of rawhide he cut and a thin nail as a needle. He even fashioned fishing nets out of goat intestines.
At one point, Selkirk spotted a French ship, and tried to signal them, but apparently remained unseen. On another occasion, a Spanish ship anchored offshore. But Spain and England were at war, and Selkirk's original mission before he became a castaway was to attack any Spanish galleons he came across, so he didn't attempt to signal them. The Spanish, however, managed to spot him anyway, and chased him through the forest. He only managed to escape by climbing a tree and hiding in its top until they sailed away.