Almost any signal repeated three times will serve as a distress signal, wait one minute in between each group of three signals.
Build signal fires in a open clearing, in a triangle shape equal distances apart. Keep a stock of items that creates smoke
Smoke not only helps the pilot of a rescue aircraft find you, it also shows the surface wind direction. Make sure that the smoke is downwind of the landing site and of any panel codes that you have laid out so that it dose not obscure them from above.
Matches are the easiest way to start a fire. Carry the non-safety ‘strike anywhere’ type and as many as possible. Pack them in a waterproof container so that the cannot rub or rattle and accidentally ignite. Waterproofing the matches themselves do both jobs.
Some people split all their matches in half and it has been claimed that one can be successfully divided into six. But do NOT risk wasting them - one that works is more use than six that don’t!