Allah Taãla says in the Noble Qurãn, 'You are the best of nations sent to man. You command good and forbid evil and you believe in Allah'. (Aali Imraan).
Allah Taãla states that one reason for this Ummah being titled as the best of Ummah, is the practice of commanding good and preventing evil'.
Making du’a is an act of worship; directing, one’s worship to other than Allah alone is an act of major shirk.
2nd Manner: Praising Allah at the beginning of the du’a and asking Allah to praise His Prophet at the end of it. Fudalah b. 'Ubaid reported that the Prophet (may Allah praise him) heard a man supplicating during prayer: the man prayed “O Allah, forgive me and have mercy on me.” So the Prophet (may Allah praise him) told him, “You were hasty. When you pray, praise Allah, ask Allah to exalt my mention, then ask Allah.” Another man praised Allah and asked Allah to exalt the mention of His prophet (may Allah praise him) so he (may Allah praise him) said: “O supplicant, ask Allah and your prayer will be answered.” [Narrated by at-Tirmidhi]
Buraidah reported that the Prophet (may Allah praise him) heard a man saying, "O Allah, I ask You, I bear witness that there is no god but You, the One, the As-Samadh (the One upon Whom all creatures depend). He begets not, nor was He begotten; and there is none like unto Him."The Prophet (may Allah praise him) said, "You have asked Allah by His Greatest Name. When one asks Him by this name, He gives, what one desires, and when supplicated by this name He answers." (Reported by Abu Dawud and Tirmidhi, who regards it a sound hadith) Ibn Mas`ud (May Allah be pleased with him) said, "Allah does not accept du’a from the conceited, the one who flaunts and the one who is not serious, (He accepts only) from a person who praises and asks from his heart."
3rd Manner: Repenting to Allah The person should repent for all of their sins and sincerely beg for Allah’s forgiveness.
4th Manner: Yaqeen (Certainty) and not being hasty The person should be certain that their du’a will be answered. The Prophet (may Allah praise him) said: “Ask Allah with certainty that He will answer your prayers, and know that Allah will not accept the supplication from an absent heart.” (at-Tirmidhi) The Prophet (may Allah praise him) said: “When you ask Allah, ask with confidence.” Abu Hurairah also reported that the Prophet (may Allah praise him) said: "None of you should say, 'O Allah, forgive me if You wish, (or) O Allah, have mercy on me if you wish.' Rather you should be firm in your request, for (Allah does whatever He wishes) and no one can force Him to do otherwise." Some of the early Muslims used to say that the supplicant should be like a child when you ask Allah, crying until you are answered.
Abu Hurayrah reported that the Prophet (may Allah praise him) said: “The person’s supplication will be answered unless he asks for sin or severing the ties of kinship, except if the person is hasty.”
Then the Prophet (may Allah praise him) was asked about hastiness. So the Prophet (may Allah praise him) described it as: “The person says, ‘I asked, and I have not seen the answer.’ Then he leaves dua.” [Muslim] `Umar (May Allah be please with him) said: "I do not carry the worry of acceptance but the worry of du’a. If I am inspired on how du’a is made, acceptance will accompany it."
`Aisha (May Allah be pleased with her) said: "No believer makes du’a and it is wasted. Either it is granted here in this world or deposited for him in the Hereafter as long as he does not get frustrated."
5th Manner: Asking Allah three times Abdullah ibn Mas'ud reported that the Prophet (may Allah praise him) loved to repeat his supplication three times, and pray for forgiveness three times. (Abu Dawud)
The Prophet (may Allah praise him) said: “If you ask Allah for the Jannah (The Heavenly Gardens) three times, the Jannah will say, ‘O Allah, make him enter Jannah.’ And if you ask Allah to protect you from hellfire three times, hellfire will say, ‘O Allah, protect him from the hellfire.’”
Wa Alaikum Assalaam Wa Rahmatullahe Wa barakatuh!.