Unicorns, drowning, and parts of speech

This is some of the best writing advice I ever received (and it came in a cute little book not much bigger than a matchbox):

When you are flailing your arms in the air and things are letting you drown, you should jot it down.

Instead of smacking on a frown, you should jot it down.

Oh look: a verb and a noun. You should jot it down.

Walking past a unicorn with a candy crown, you should jot it down.

When you are saying goodbye to friends and a town, you should jot it down.