What to say and do after committing a sin?

Whoever commits a sin should perform ablution well, then stand and pray two rak'ahs and ask Allah the Most High for forgiveness, and Allah the Most High forgives him.

1. Sahih, Sunan Abi Dawud, no. (1521), Sunan at-Tirmidhi, no. (406), Sunan Ibn Majah (1395), and al-Albani graded it Sahih in “Sahih Abi Dawud (5/252)” no. (1361)