First, set up a miniature "grave" in a sandy beach for your sexual partner to lie in. Proceed to cover your partner's entire body, excluding the genitalia and face. Wait for your partner to fall asleep. When the moment is right begin to fornicate with your partner, appearing to onlookers that you are merely sexing the sand.
Bob: "So I hear you're bringing Natasha on a date to the beach tonight!"

Marquis: "Yo, Imma goina sandman that ho."
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