Ṣaḥīḥ reporting in supplication and praising Allah the almighty

«اللَّهُمَّ أَعِنِّي عَلَى ذِكْرِكَ، وَشُكْرِكَ، وَحُسْنِ عِبَادَتِكَ»
{وهو دعاء يُشرع قوله في التشهد الأخير قبل السلام}

alllahuma 'aeinni ealaa dhikrika, washukrika, wahusn eibadatika.

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

It is a supplication which to be said in last Tashahhud prior the salutations