A boa captain hilariously demonstrated to a tourist how to wear a life jacket.

The local spotted the pensioner trying to board the speedboat in just his swimming trunks in Krabi, Thailand, on January 30.

Stopping him on the sand, he made an amusing series of gestures to demonstrate someone drowning.

He moved his arms to mimic someone swimming before facing upwards with closed eyes and his tongue out, representing a dead man.

He then gestured a ‘no' with both hands and took an orange lifejacket from his colleague before helping the holidaymaker wear it.

Local tour guide Annita, who watched the amusing interaction, recorded it while she was also preparing to board the speedboat on a trip to nearby islands.

She said: 'It's good to see boat operators are paying more attention to safety. The way he did the safety demonstration was funny.'