Mnemonic

grandma opens her mouth wide under the moonlight and pulls a shimmering thread of silk from between her lips — she's been secretly spinning silk inside her mouth all night! Grandma is part silkworm, her cocoon glowing in the moon's pale light.
Additional thoughts
Picture grandma as a human silkworm: mouth open, moonlit thread emerging. The absurd image of grandma-as-silkworm makes it stick. Moon = nighttime spinning, mouth = where the thread exits.
Quick recall
grandma pulls silk thread from her mouth under the moon — she's a human silkworm!

Details

The keyword for 絹 is silk. This kanji refers specifically to silk fabric or cloth, the luxurious textile produced from the cocoons of silkworms. It has been a highly prized material throughout East Asian history, playing a central role in trade, culture, and craftsmanship. The character conveys the refined, smooth quality of woven silk as a finished textile product.
On'yomi
けん
Kun'yomi
きぬ

Used in vocab