It is not only the Morse code, but there are other ways to send SOS.
You will be using lights (mirrors or torches) or sound (whistle etc.).
With those materials, repeat the following sequences of 1 to 2.
(1) Keep the sign on for 10 seconds and repeat it 6 times.
(2)Turn it off for 1 min.
One sequence (1＋2) is 2 min. Use light and sound for the10 seconds.
To respond to the SOS sign, repeat the following sequences of 1 to 2. 1.
Keep the sign on for 20 seconds, 3times. 2. Turn it off for 1 min.
When you shout for help, take care not to use too much energy and damage your throat.