What Should A Person Who Forgets To Perform Sajdah Al-Sahw Do?

What should a person who forgets to perform sajdah al-sahw do?

If a person who has not performed sajdah al-sahw by mistake or forgetfulness does acts not related to the prayer such as laughing, speaking, or turning his direction away from the qiblah, after giving salam, or does not have enough time to perform sajdah al-sahw, then he will not be responsible for it. And he does not need to re-establish that prayer either. However, if he remembers to perform sajdah al-sahw before committing an act irrelevant to prayer, he immediately performs it (Kasani, Bada’i, I, 174).

Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWA