I've also heard losing a mop or bucket overboard is a bad omen.
When starting a voyage, don't look back to the shore.
Wearing the clothes of a dead man before the voyage has ended is bad luck.
Never speak the name of the dead, it would call them to you.
A knife stuck into the main mast would summon a favorable wind.
Never say, drown or sink while at sea.
Some pirates tattooed open eyes on their eyelids so as to never be caught asleep.
An earring would boost your stamina and endurance.
Killing a seagull or albatross would bring death, the only counter to this was to wear the bird around your neck until landfall, then give the bird a Christian burial. If not, the bird was hung about the offenders neck and he and the bird were tossed to the sea, for a discussion and trial by Neptune. " Rhyme of the Ancient Mariner"