The Messenger of Allah ﷺ said, "The best things to use for changing this gray hair are henna and katam."
حدثنا الحسن بن علي حدثنا عبد الرزاق حدثنا معمر عن سعيد الجريري عن عبد الله بن بريدة عن أبي الأسود الديلي
قال رسول الله ﷺ إن أحسن ما غير به هذا الشيب الحناء والكتم
[Its chain of transmission is sahih]Reported by Tirmidhi in his chapters on clothing, the chapter on what has been said about dyeing hair, hadith no. 1753, from the hadith of Abdullah bin Burayda, with this wording, and he said, "Hasan sahih." Ibn Majah also reported it, hadith no. 3622, as did Nasai, no. 5083, and Ibn Hibban graded it sahih, no. 1475. It is also found in the Musannaf of Abdul-Razzaq (Jami Maamar), hadith no. 20174, and Maamar's hearing from Jareeri was before his memory changed (al-Kawakib al-Nayyirat, p. 36).