Etiquette Of Making Dua

And when My servants ask you, [O Muhammad], concerning Me - indeed I am near. I respond to the invocation of the supplicant when he calls upon Me. So let them respond to Me [by obedience] and believe in Me that they may be [rightly] guided.
Surah Al Baqarah 2:186

"And to Allah belong the best names, so invoke Him by them."
Surat Al-Araf, 7:180

Indeed, Allah will not change the condition of a people until they change what is in themselves. 
Surah Ar-Ra'd 13:11

----- Etiquette of Making Dua -----

 Direct Dua only towards Allah, (towards anything or anyone else is shirk)

 Wudu (if convenient)

 Facing towards the Qiblah

 Your Lord, may He be blessed and exalted, is Kind and Most Generous, and He is too kind to let His slave, if he raises his hands to Him, bring them back empty.

 Use 99 names attributes of Allah (some examples)

Ar-Rahman - The All-Compassionate
Ar-Rahim - The All-Merciful
Al-Hakim - The Perfectly Wise
Al-Kabir - The Greatest
Al-Jalil - The Mighty
Al-Karim - The Generous
Al-Hayy - The Ever Living One
Al-Qayyum - The Self-Existing One
Al-Ghaffar - The Forgiving
Al-Ghafur - The Forgiver and Hider of Faults
Al-Hakam - The Judge
As-Sami - The Hearer of All
Al-Basir - The Seer of All
Ash-Shahid- The Witness
Al-Mujib - The Responder to Prayer
As-Samad - The Satisfier of All Needs
Malik-al-Mulk - The Owner of All
Dhu-al-Jalal wa-al-Ikram - The Lord of Majesty and Bounty

 Praise Allah (Surah Fathia) and Dhikr

 Make any Dua 3 times

 Make Dua Routinely

 Ask for forgiveness (Astaghfirullah)

 Send blessing to Prophet Muhammad(ﷺ) (Durood Ibrahim)
Allahumma Salli Ala Muhammadiw Wa Ala Aali Muhammadin Kamaa Sallaita Ala Ibrahima Wa Ala Aali Ibrahima Innaka Hamidum Majid. Allahumma Baarik Ala Muhammadiw Wa Ala Aali Muhammadin Kamaa Baarakta Ala Ibrahima Wa Ala Aali Ibrahima Innaka Hamidum Majid.

O Allah, let Your Blessings come upon Muhammad and the family of Muhammad, as you have blessed Ibrahim and his family. Truly, You are Praiseworthy and Glorious. Allah, bless Muhammad and the family of Muhammad, as you have blessed Ibrahim and his family. Truly, You are Praiseworthy and Glorious.

 Recite Dua of Prophet Yunus (AS)

La iIlaha iIlla Anta Subhanaka inni Kuntu Mina Az-Zalimin
“La ilaha illa Anta [none has the right to be worshipped but You (O Allah)], Glorified (and Exalted) are You [above all that (evil) they associate with You]. Truly, I have been of the wrong-doers

 Ask for Jannatul Firdous and refuge from Hell

Allahuma Adkhilni Jannat il Firdous
(Recite 3 times)
(Oh Allah grant me Jannat Al Firdous)

Allahumma inni Asalukal Jannah
(Recite 3 times)
O Allah, I ask You of Paradise

Allah Humma Ajirni Minan Naar
(Recite 3 times)
(O Allah, save me from the fire)

 Allahumma-Ghfirli Warhamni Wa 'Afini Warzuqni 
(O Allah, forgive me, have mercy on me, keep me safe and sound and grant me provision)

 Rabbana Atina Fid-Dunya Hasanatan Wa Fil 'Akhirati Hasanatan Waqina 'Azaban Nar
(Our Lord! Grant us good in this world and good in the hereafter, and save us from the chastisement of the fire) [2:201]

 Ask Dua for others (angels will say Ameen for you also)

 Halal Earnings 
e.g. income NOT from Riba, income from unlawful means (keep food, dress and house under halal income).

 Keep away from Bidah (innovation in religion)

 Make Dua that has goodness for yourself and for others

 Be patient in Dua Acceptance

 Be sincere in your Dua

 Be Humble while asking Allah

 Be certain that Dua will be accepted (Tawakkal upon Allah)

 When making Dua have faith that whatever Allah will give will be better and will ward off anything that is not good for us.