بِسْمِ اللهِ الرَّحْمٰنِ الرَّحِيْمِ

 اللَّهُمَّ صَلِّ عَلَى مُحَمَّدٍ وَعَلَى آلِ مُحَمَّدٍ

Allaahumma salli 'ala Muhammad wa 'ala aali Muhammad

O Allaah! Praise Muhammad, and on the family of Muhammad

For the full thing: 

اللَّهُمَّ صَلِّ عَلَى مُحَمَّدٍ وَعَلَى آلِ مُحَمَّدٍ كَمَا صَلَّيْتَ عَلَى إِبْرَاهِيمَ وَعَلَى آلِ إِبْرَاهِيمَ إِنَّكَ حَمِيدٌ مَجِيدٌ. 

اللَّهُمَّ بَارِكْ عَلَى مُحَمَّدٍ وَعَلَى آلِ مُحَمَّدٍ كَمَا بَارَكْتَ عَلَى إِبْرَاهِيمَ وَعَلَى آلِ إِبْرَاهِيمَ إِنَّكَ حَمِيدٌ مَجِيدٌ

Allaahumma salli 'ala Muhammad wa 'ala aali Muhammad kama sallaita 'ala Ibraaheem wa 'ala aali Ibraaheem innaka Hameedun Majeed, wabaarik 'ala Muhammad wa 'ala aali Muhamaad kama baarakta 'ala Ibraaheem wa 'ala aali Ibraaheem innaka Hameedun Majeed. 

O Allaah! Praise Muhammad, and on the family of Muhammad, as You Praised Ibraaheem, and the family of Ibraaheem; You are indeed Worthy of Praise, Full of Glory. And send blessings on Muhammad, and on the family of Muhammad, as you sent blessings on Ibraaheem, and the family of Ibraaheem; You are indeed Worthy of Praise, Full of Glory.

Source(s):http://www.understand-islam.net/salat/06...