After the last tashahhud & before salam #5

اَللّٰهُمَّ أَعِنِّيْ عَلَى ذِكْرِكَ، وَشُكْرِكَ، وَحُسْنِ عِبَادَتِكَ

O Allah, help me to remember You, to give You thanks, and to perform Your worship in the best manner.

Allaahumma 'a'innee 'alaa thikrika, wa shukrika, wahusni 'ibaadatika.