Answered by Shaykh Faraz Rabbani
Question: How does one perform the forgetfulness prostration?
Answer: In the Name of Allah, the Benevolent, the Merciful
Assalamu alaikum wa rahmatullah,
I pray this finds you in the best of health and spirits.
For the forgetfulness prostration (which is necessary if a necessary [wajib] action was left forgetfully, and for nothing else):
1. In the final sitting, recite the tashahhud;
2. Give one salam, to the right;
3. Perform two prostrations, with their sunnas;
4. Sit and repeat the final sitting, in full–reciting the tashahhud, sending blessings, and making supplication (dua); and then
5. End with two salams.
And Allah alone gives success.
Faraz Rabbani