ENOfficial
It was narrated that 'Abdullah bin Buraidah said: "The Messenger of Allah (ﷺ) said: 'The best things with which you can change gray hair are Henna and Katam.'"
Source: sunnah.com
Other translations
Arabic
أَخْبَرَنَا حُمَيْدُ بْنُ مَسْعَدَةَ، قَالَ حَدَّثَنَا عَبْدُ الْوَارِثِ، قَالَ حَدَّثَنَا الْجُرَيْرِيُّ، عَنْ عَبْدِ اللَّهِ بْنِ بُرَيْدَةَ، قَالَ قَالَ رَسُولُ اللَّهِ صلى الله عليه وسلم " إِنَّ أَحْسَنَ مَا غَيَّرْتُمْ بِهِ الشَّيْبَ الْحِنَّاءُ وَالْكَتَمُ " .
sunnah.com