Friday is also the day on which one of the greatest verses in the Quran was revealed. “This day, I have perfected your religion for you, completed My Favor upon you, and have chosen Islam as your religion.” (Quran 5:3)

From the traditions of Prophet Muhammad, may the mercy and blessings of God be upon him, we learn that “The best day in the sight of God is Friday, the day of congregation” Congregational prayers (obligatory for men) are one of the most strongly emphasized duties in Islam. It is a time when Muslims come together to worship One God, and find strength and comfort by standing shoulder to shoulder and reaffirming their faith and devotion to Him.

“O you who believe! When the call to prayer is proclaimed on Friday hasten earnestly to the remembrance of God, and leave aside business. That is best for you if you but knew.” (Quran 62:9)

"Then when the (Jumu`ah) Salat is ended, you may disperse through the land, and seek the Bounty of Allah (by working), and remember Allah much: that you may be successful.'' (62:10)

Friday is the best Day of the week. It is the Mothers of all days and the most virtuous in the sight of the sight of Allah it has more greatness than Eid-ul-Fitr and Eid –ul-Adha (Reported in Ibn Majah)

Only that believer is graced with the blessings and benefits of Friday, who looks forward for it most anxiously and eagerly ; and wretched is the negligent one who is least interested in it and who does not even know in the morning which day has dawned ( Imam Ghazali says Ihya ul-Ulum)

Thus We should make preparations for Jummah from Thursday night, (which is Friday night islamically because is Islam we start with Night and end with the day until the followng night-Maghrib) The person who will receive the most benefit on Friday will be that person who waits for it and makes preparations for it from Thursday.

The Main merits of holy day of Friday are the first six;

1. Allah created Adam alayhis salaam on Friday and he was granted entry into jannah on Friday.

2. Adam alayhis salaam was sent to earth on this day as his vicegerent.

3. Adam alayhis salaam died on a Friday.

4. There is a blessed hour on Friday during which a person is granted anything lawful and good by Allah that he prays for.

5. The blessed hour on Friday is such that Duas are answered and accepted,(from my research its an hour in 'Asr to Maghrib)

6. The Day of Qiyamah-Resurrection will be on a Friday. It is on this day that the Trumpet will be blown on Friday; There is neither any angels nearest to Allah nor any heaven nor the earth nor the wind and a sea but all of them fear the Day of Jummah,that is why everything in the heavens and the earth including God's most favorite angels and mountains, rivers etc. stand in awe of Friday.

Its called jumm'ah because sayyiduna Adam alayhis salaam was put togehter on this day, meaning its the day he was born-This Milad. So whoever performs the Jumm'ah salah is actually celebrating Eid Meelid un nabi of sayyiduna Adam alayhis salaam. And "O Muslims! Allah Ta'ala has made this day (Friday) a day of 'Eid'. So have a bath on this day, whoever has perfume should apply it, and use the miswaak." (Ibn Majah).The point now to those who object to Eid Milad-un-nabi of the Sayyid of the Children of Adam, Sayyiduna Muhammad sallallahu alayhi wa sallam, is simple either stop praying Jumm'ah which is Kufr or either be quiet with your Munafiq-hypocritical behaviour and please learn your Deen correctly or celebrate the Milad un-nabi of Sayyiduna Muhammad sallallahu alayhi wa sallam which is the day he was born and is the greatest of all days.

7. Friday is Sayyid-The Master of the week, the best of days, like Ramadhan is Sayyid of the Month and Surah Baraqah is the Sayyid of the Quran.

8. In certain aspects the rank of the night of jumu'ah is even higher than Laylatul Qadr.

10 .One of the reasons for this is that it was on this night that Rasulullah sallallahu alayhi wa sallam appeared in the womb of his mother.

600,000 souls are freed from the fire of Hell each Hour, throughout the day and night of every Friday, even though all of them have deserved condemnation to the fire.The birds and insects meet with one another on Friday and say "peace be upon you , may it be a good day".

11. Rasulullah's sallallahu alayhi wa sallam appearance in this world was a cause of so much good and blessings both in this world and in the hereafter that they cannot be enumerated.

12. There is such an hour on Friday that if any Muslim makes dua in it, his dua will definitely be accepted." (Bukhari, Muslim)

13. Rasulullah sallallahu alayhi wa sallam said: Of all the days, Friday is the most virtuous. It is on this day that the trumpet will be blown. Send abundant durood upon me on Fridays because they are presented to me on that day."

14. The word "shaahid" refers to Friday. There is no day more virtuous than Friday. There is such an hour in this day that no Muslim will make dua in it except that his dua will be accepted. And he does not seek protection from anything except that Allah Ta'ala will grant him protection." (Tirmidhi)

15. The word "shaahid" appears in Surah Burooj. Allah Ta'ala has taken an oath of that day. He says in the Quran: "By the sky in which there are constellations. By the promised day (of judgement). By the day that witnesses (Friday), and the day that is witnessed (day of Arafah)."

16. "Friday is the "mother" of all days and the most virtuous in the sight of Allah Ta'ala. In the sight of Allah Ta'ala it has more greatness than Eid ul-Fitr and Eid ul-Ad'haa." (Ibn Majah)

17. The Muslim who passes away on the night or during the day of Friday, Allah Ta'ala saves him from the punishment of the grave." (Tirmidhi)

Surah al Mulk is the protector from the torment of the grave, so if you dont die on friday and wont know when we are going to die, its best to read every and memorise this surah also. There is a Surah which will plead for its reciter till it causes him to enter paradise (Tabarakallahi Biyadihil Mulk).

18."The best day on which the sun has risen is Friday. On that day Adam was created, he was admitted to Jannah, and he was expelled therefrom.''[Muslim].

19. "If anyone performs Wudu' properly, then comes to the Friday prayer, listens to the Khutbah (religious talk) attentively and keeps silent, his (minor) sins between that Friday and the following Friday will be forgiven, with the addition of three more days; but he who touches pebbles has caused an interruption.''

20. "Either some people (i.e., hypocrites) stop neglecting the Friday prayers, or Allah will seal their hearts and they will be among the heedless.''

21. Taking a bath (before coming to Friday prayers) is obligatory on every adult.

22. "It suffices to perform Wudu' properly for the Friday prayer; but it is better to take a bath.''

23. Every afternoon, the heat of jahannam is increased. However, through the blessings of jumu'ah, this will not be done on Fridays. (Ihyaa ul-Uloom)

24. The following verse : "This day, I have completed your Deen for you." A Jew was sitting near him. On hearing this verse being recited he remarked : "If this verse was revealed to us, we would have celebrated that day as a day of eid." Ibne Abbas radiallahu anhu replied : "This verse was revealed on two eids, i.e. on the day of jumu'ah and the day of arafah." In other words, what is the need for us to make that day into a day of eid when it was already a day of two eids?

25. "O Muslims! Allah Ta'ala has made this day(Friday) a day of 'Eid'. So have a bath on this day, whoever has perfume should apply it, and use the miswaak." (Ibn Majah)

26. "He who takes a bath on Friday, like the bath for ceremonial purity, and then goes (to the mosque), he is like one who offers a camel as a sacrifice to seek the Pleasure of Allah; and he who comes at the second hour is like one who offers a cow to win the Pleasure of Allah; and he who comes at the third hour is like one who offers a ram with horns (in sacrifice); and he who comes at the fourth hour is like one who offers a hen; and he who comes at the fifth hour is like one who offers an egg. And when the Imam ascends the pulpit, the angels (who write the names of those who come to the mosque before the coming of the Imam) close (their record) in order to listen to the Khutbah.''

The bath of Friday, pull out every sin of the man from its root.

One should understand jumm'ah is a day of Eid and so take a bath be neat and tidy, trim your hair or nails and apply perfume and deodorant and also wear a Turban. A tadition says "The Angels invoke blessings upon those who wear a turban on Friday".

THUS THE PERMISSIBILITY OF CELEBRATING EID MILAD-UN-NABI

Now with all this in Mind, that is All the above expressed the virtues of Jummah (Friday) by also saying that Adam (alaihissalaam) was born on that day. Therefore, imagine the virtue of that day when Rasoolullah (sallal laahu alaihi wasallam) was born! Who is the greatest of the all.

One's deeds are shown to Allah on Monday and Thursday, and they are shown to Prophets as well as fathers and mothers on Fridays, at which time they rejoice for the good deeds, and the latter increase the brightness and light of their faces. Therefore be wary of Allah and do not harm your dead."

https://www.quora.com/Why-is-Friday-a-special-day-in-Islam