DUROOD ON FRIDAY
It has been reported in the hadeeth shareef that Rasulullah (Sallallahu Alayhi Wasallam) said: "Send durood and salaam upon me in abundance on Friday because your durood and salaam is presented before me (especially on the day of Friday)."
It has been narrated in another hadeeth that whoever sends durood on me on Friday his durood is (especially) and most certainly presented before me.
The shortest and simplest form of Durood is
صَلَّى اللهُ عَلَيْهِ وَسَلَّم
Transliteration: Sall-Allahu alayhi wasallam
Translation: Peace and Blessings be upon him (Prophet Muhammad)
Read more about Durood.