O Allah, Help Me to Remember You
اللَّهُمَّ أَعِنِّي عَلَىٰ ذِكْرِكَ وَشُكْرِكَ وَحُسْنِ عِبَادَتِكَ
Allahumma a'inni 'ala dhikrika wa shukrika wa husni 'ibadatik.
O Allah, help me to remember You, to thank You, and to worship You well.
What it means
Even remembering Allah is something you need His help to do. This dua admits that, and asks for the three things that make up a good religious life: a tongue that remembers, a heart that is grateful, and worship done properly rather than merely completed.
When and how
Say it once after the salam of every prayer, as the Prophet ﷺ advised Muadh.
Its virtue
The Prophet ﷺ took Muadh ibn Jabal by the hand and told him he loved him, then instructed him never to leave saying this at the end of every prayer, reported in Sunan Abi Dawud 1522.
Source
Abu Dawud 1522sahih