Musnad Ahmad 1153:1118

Muhammad ibn Ja‘far narrated to us, Shu‘bah narrated to us, from Jabir, from Yazid ibn Murrah, from Lamis, that she said: I asked ‘Aishah. I said to her: "May a woman make oil to make herself beloved to her husband?" She said: "Remove from yourself that which Allah, the Mighty and Majestic, does not look at." She said: And a woman said to ‘Aishah: "O Mother." ‘Aishah said: "I am not a mother, but I am your sister." ‘Aishah said: "The Messenger of Allah, may Allah bless him and grant him peace, used to mix the twenty [nights] with prayer and sleep. But when the ten [final nights] came, he would tuck up [his garments], tighten his waist-wrapper—or tighten the wrapper—and tuck up."