How Should Enjoining Ma'ruf (Good) be in Ramadan?  

Do you live alone in this world? No, you  do not. You live with your children, wife, partner at work, colleague in the department, or friend.  If one of those whom you live with, commits a mistake, you should tell him that kindly and in private. 

In fact, giving advice to other people in public is a scandal not a piece of advice, so if you want to advise someone concerning a mistake or a sin he commits, you can kindly say, "Doing such and such a thing is not permissible", "Doing this or that displeases Allah, Exalted and Sublime be He" or "These words are unacceptable by Allah, Exalted and Sublime be He". The main point is giving advice to others in a polite and humble manner. 

Pay attention to the following Ayah, please: 

("Go, both of you, to Fir'aun (Pharaoh)…)

[Ta-Ha, 43]

In the above Ayah, Allah the Almighty refers to the most aggressive Kafir (disbeliever) on earth who said as Allah the Almighty narrates: 

(Saying: "I am your lord, most high")

[An-Nazi'aat, 24]

He also said as Allah the Almighty narrates: 

(Fir'aun (Pharaoh) said: "O chiefs! I know not that you have an ilah (a god) other than me, so kindle for me (a fire)…)

[Al-Qasas, 38]

Allah the Almighty says: 

("And speak to him mildly…)

[Ta-Ha, 43]

Allah the Almighty ordered them (Noble Prophets Musa and Harun) to speak mildly to the   worst disbeliever on earth, so why should you be harsh on your fellow brother in faith while advising him?    

Once a person advised his fellow brother harshly, so the latter said, "Why are you so harsh on me? Allah the Almighty sent  Musa, peace be upon him who is better than you to       (Fir'aun), who is worse than me, yet He asked him to speak mildly to him."