What were Imam Khomeini's recommendations during holy month of Ramadan?

The Greatest Jihad (Combat with the Self), Text, Page: 22

Imam used to perform all optional and obligatory prayers during Ramadan

It has been reported that Imam Khomeini used to perform all optional and obligatory prayers in perfect manners while observing the fast during the month of Ramadan.

The Supplication for the 1th Day of Ramadan

Imam Khomeini and divine spirituality in the month of Ramadan.

Imam always remembered God the Almighty during all thin and thick times

A memoirs by Haj Ahmed Agha Khomeini – Imam's son

Imam would stay awake until dawn during Ramadan

Hujjatal Islam Nasari

When the Prophet reviews your deeds, Imam Khomeini explained

Imam Khomeini says when the Prophet reviews your deeds and he sees how many errors and sins there are, how upset and distressed will he be?

Imam Khomeini advised believer to completely concentrate attention on God Almighty

Imam Khomeini has said it requires extra hard practice, going to some lengths, spiritual exercises, perseverance, and discipline, until one is able to fix one’s attention completely on nothing but God and cut himself off from all else.