Abu Muhammad Ka'b bin 'Ujrah (May Allah be pleased with him) reported

The Prophet (ﷺ) came to us and we asked him, "O Messenger of Allah , we already know how to greet you (i.e., say As-salamu 'alaikum), but how should we supplicate for you?" He (ﷺ) said, "Say: 'Allahumma salli 'ala Muhammadin, wa 'ala 'ali Muhammadin, kama sallaita 'ala 'ali Ibrahima, innaka Hamidum Majid. Allahumma barik 'ala Muhammadin, wa 'ala 'ali Muhammadin, kama barakta 'ala 'ali Ibrahima, innaka Hamidum Majid [O Allah, exalt the mention of Muhammad and the family of Muhammad as you exalted the family of Ibrahim. You are Praised and Glorious. O Allah, bless Muhammad and the family of Muhammad as You blessed the family of Ibrahim. You are Praised and Glorious."'

[Al-Bukhari and Muslim].