The Gerber Bear Grylls survival knife implemented an interesting idea of including these signals on the back of its sheath.



However you do it, it does seem like it would be a good idea to include a small, quick reference of these signals on your person somehow.
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Victory awaits him who has everything in order — luck, people call it. Defeat is certain for him who has neglected to take the necessary precautions in time; this is called bad luck. Roald Amundsen