In his well-known book, The Reliance of the Traveler, Ahmad ibn Naqib Al-Misri, states:
“To prostrate after reciting certain Qur’anic verses that refer to or command Sujud is Sunnah. This can be done by the person who recites and whoever listens to him. [In this context, we recall the Hadith narrated by Ibn `Umar, may Allah be pleased with them both, who said, “The Prophet, peace and blessings be upon him, used to read Qur’an, and whenever he read a Surah which contained a prostration, he would prostrate and we would prostrate with him so that some of us could not find a place to lay their forehead.” (Reported by Muslim)]
Recital prostration can be done by a person praying alone or behind an Imam, but one’s Prayer becomes invalidated if one intentionally, being aware of its prohibition, recites a verse just for the sake of performing the prostration, with the exception of Surat As-Sajdah (Qur’an 32) recited in the Fajr Prayer on Friday.
However, there is nothing wrong in performing prostration if one, in the course of reciting some verses in Prayer, recites a verse in which prostration is mentioned.
It’s not for Imam or a person praying behind him to perform Qur’anic recital prostration just upon hearing a person reciting a verse in which prostration is mentioned. Doing so will invalidate the Prayer.
Given that a person praying behind Imam follows him in every aspect of Prayer, then he should prostrate whenever he sees Imam offering the recital prostration. Failing to do so invalidates his Prayer, so does his prostration for his own recitation of the Qur’an, or for the recitation of someone besides Imam.
There are fourteen Qur’anic verses that call for prostration. In Prayer, before one prostrates for such verses, it is recommended to say “Allahu Akbar“, and the same applies when rising from prostration. Then, if one performs the Prayer in standing position, one should return to standing after offering the prostration.
But if one performs Prayer in sitting position (say for instance when performing supererogatory Prayer), one should also return to the previous sitting position, and continue reciting the Qur’anic verses before one bows (this is recommended).
Outside Prayer, when one offers recital prostration, it is obligatory to say an opening formula, Allahu Akbar and end it with Salams. The four integrals of the Qur’anic recital prostration (outside Prayer) are:
(a) the intention,
(b) the opening Allahu Akbar,
(c) the prostration,
(d) and the final Salams (which can only be uttered in a sitting position).
Whether in or out of Prayer, the things that invalidate a normal Prayer invalidate the recital prostration as well, and the conditions that govern the Prayer also govern the recital prostration.
If one delays the recital prostration just for a short period (less than the time for offering two brief, medium-length Rak`as), then one is still entitled to prostrate. If longer than that, one does not need to make up for it.
When one repeats a prostration verse within one sitting or within one Rak`ah and one has failed to perform it at first, it is enough to perform it at the second time, just with a single prostration.”