you avoid the major sins you have been forbidden, We shall wipe away your minor misdeeds” (al-Nisāʾ 4:31).
Shaykh al-Islām (Ibn Taymiyyah) said, “Remembrance of Allah (dhikr) is among the very best acts of worship.” ʿĀʾishah, may Allah be pleased with her, added, “The remembrance uttered after leaving the prayer is like wiping a mirror once it has been polished, for the prayer itself polishes the heart.”
Saying the prescribed remembrances after the obligatory prayer is not obligatory; should someone wish to leave, no blame attaches to him. Even so, the follower ought not to rise until the imām has turned away from the qiblah, and it is unbecoming for the imām to remain facing the qiblah after the salām for longer than it takes to seek forgiveness three times and say: “Allāhumma anta al-salām, wa minka al-salām, tabārakta yā dhā al-jalāli wa-l-ikrām – O Allah, You are Peace and from You comes peace; blessed are You, Lord of Majesty and Honor.”
8 – Counting the tasbīḥ (saying “subḥān Allah”) on one’s fingers is a Sunnah. The Prophet ﷺ said to the women: “Glorify Allah and count on your fingers, for they will be questioned and made to speak” (Ahmad 26549; al-Tirmidhī 3583).
9 – In some narrations recorded by the two Ṣaḥīḥs, completing the hundred is done by saying: “Lā ilāha illā Allah …” and so on. Other reports stipulate that the takbīr (saying “Allāhu akbar”) is to be said thirty-four times. A version in Muslim of this very ḥadīth states: “After every prayer you say ‘subḥān Allah’, ‘al-ḥamdu lillāh’, and ‘Allāhu akbar’ thirty-three times—eleven, eleven, and eleven—making a total of thirty-three.” Another narration in al-Bukhārī (6329) reads: “After every prayer you say ‘subḥān Allah’ ten times.” In Fatḥ al-Bārī, Ibn Ḥajar quotes al-Baghawī in Sharḥ al-Sunnah as reconciling these variations by suggesting that the Prophet’s instructions were issued at different times, or that they are offered as alternative options, or that the counts differ according to one’s circumstances.
The present editor—may Allah pardon him—remarks: Since these ḥadīths are all authentic with their respective numbers, one should perform this form on one occasion and that form on another. The shorter tally may be used when time is tight so that the worshipper does not miss the Sunnah and its virtue. Allah is Gentle with His servants.
As for combining all of the narrations, or more than one of them, in a single prayer, that is not recommended.