OK, this mnemonic is a bit of a stretch:
The right-side part of 喋 looks like 葉, which is a kanji in the word, 'word'=言葉.
|( を or と ) しゃべ＊る||
You talk to me with your MOUTH, about a leaf of a pretty FLOWER.
tone of voice
調子 口調 喋り方