Information taken from:
Hadith – Bukhari 4:674, Narrated Humaid bin ‘Abdur-Rahman , see also Bukhari 4:694, 7:816
That he heard Muawiya bin Abi Sufyan (talking) on the pulpit in the year when he performed the Hajj. He took a tuft of hair that was in the hand of an orderly and said, “O people of Medina! Where are your learned men? I heard the Prophet forbidding such a thing as this (i.e. false hair) and he used to say, ‘The Israelis were destroyed when their ladies practiced this habit (of using false hair to lengthen their locks).“
Hadith – Bukhari 7:133, Narrated ‘Aisha , see also Bukhari 7:818
An Ansari woman gave her daughter in marriage and the hair of the latter started falling out. The Ansari women came to the Prophet and mentioned that to him and said, “Her (my daughter’s) husband suggested that I should let her wear false hair.” The Prophet said, “No, (don’t do that) for Allah sends His curses upon such ladies who lengthen their hair artificially.“
Hadith – Muslim, Narrated Jabir ibn Adullah
Allah’s Apostle reprimanded that a woman should add anything to her head (in the form of artificial hair).
Hadith – Bukhari 7:803, Narrated Ubaidullah bin Hafs
that ‘Umar bin Nafi’ told him that Nafi’, Maula ‘Abdullah had heard ‘Umar saying, “I heard Allah’s Apostle forbidding Al-Qaza’.” ‘Ubaidullah added: I said, “What is Al-Qaza’?” ‘Ubaidullah pointed (towards his head) to show us and added, “Nafi’ said, ‘It is when a boy has his head shaved leaving a tuft of hair here and a tuft of hair there.” Ubaidullah pointed towards his forehead and the sides of his head. ‘Ubaidullah was asked, “Does this apply to both girls and boys?” He said, “I don’t know,” but Nafi’ said, -The boy.” ‘Ubaidullah added, “I asked Nafi’ again, and he said, ‘As for leaving hair on the temples and the back part of the boy’s head, there is no harm, but Al-Qaza’ is to leave a tuft of hair on his forehead unshaved while there is no hair on the rest of his head, and also to leave hair on either side of his head.’ “
When to Cut Hair
Hadith – Muslim, Narrated Anas ibn Malik
A time limit has been prescribed for us for clipping the moustache, cutting the nails, plucking hair under the armpits, shaving the pubes, that it should not be neglected far more than forty nights.
Braided (Plaited) Hair
Hadith – Muslim, Narrated Umm Salamah
I said: Messenger of Allah, I am a woman who has closely plaited hair on my head; should I undo it for taking a bath, because of sexual intercourse? He (the Prophet ) said: No, it is enough for you to throw three handfuls of water on your head and then pour water over yourself, and you shall be purified.
Hadith – Muslim, Narrated Abdullah ibn Abbas
Ibn Abbas saw Abdullah ibn al-Harith observing the prayer and (his hair) was plaited behind his head. He (Abdullah ibn Abbas) stood up and unfolded them. While going back (from the prayer) he met Ibn Abbas and said to him: why is it that you touched my head? He (Ibn Abbas) replied: (The man who observes prayer with plaited hair) is like one who prays with his hands tied behind.
Hadith – Bukhari 4:668, Narrated Abu Huraira , see also Bukhari 7:786
Allah’s Apostle said, “The Jews and the Christians do not dye (their grey hair), so you shall do the opposite of what they do (i.e. dye your grey hair and beards).”
Hadith – Muslim, Narrated Jabir ibn Abdullah
When AbuQuhafah (father of AbuBakr) came in the Year of Victory or on the Day of Victory (to the Prophet to pledge his allegiance to him) his head and his beard were white like hyssop. He (the Prophet ) commanded or the women were commanded by him that they should change this with something (that the color of his hair should be changed).
Hadith – Muslim, Narrated ‘Ubaid Ibn Juraij
…And about the dyeing of hair with Hinna; no doubt I saw Allah’s Apostle dyeing his hair with it and that is why I like to dye (my hair with it)…
Is it permissible for a woman to dye the hair upon her head with black dye?
It is not permissible for a woman or other than her to colour their hair with black dye, because of the statement of the Messenger sallAllaahu ‘alayhi wa sallam:
”Change this colour, and stay away from the black (colour).” 
As for changing (the hair colour) with other than black, then no problem, or (changing it) with henna or mixed al-Katam,  so there is no problem with this if the colour changes to other than black, or between black and red.
Shaykh `Abdul-`Azeez Bin Baz
Majmoo’ Fatawa, volume.10 page.53
 Reported by Muslim is his Saheeh.
 Translators Note: ‘al-Katam’ is a plant that gives a dark colour, from the myrtle family.
Disposing of Hair after Haircuts
Hadith – Muslim, Narrated Anas ibn Malik
I saw when the Messenger of Allah got his hair cut by the barber, his Companions came round him and they eagerly wanted that no hair should fall but in the hand of a person.
Hadith – Abu Dawud, Narrated Abdullah ibn Amr ibn al-‘As
The Apostle of Allah said: Do not pluck out grey hair. If any believer grows a grey hair in Islam, he will have light on the Day of Resurrection. (This is Sufyan’s version). Yahya’s version says: Allah will record on his behalf a good deed for it, and will blot out a sin for it.
Hadith – Abu Dawud, Narrated AbuDharr
The Prophet said: The best things with which grey hair are changed are henna and katam.
Hadith – Abu Dawud, Narrated Abdullah ibn Mas’ud
The Prophet of Allah disliked ten things: Yellow colouring, meaning khaluq, dyeing grey hair, trailing the lower garment, wearing a gold signet-ring, a woman decking herself before people who are not within the prohibited degrees, throwing dice, using spells except with the Mu’awwidhatan, wearing amulets, withdrawing the penis before the semen is discharged, in the case of a woman who is wife or not a wife, and having intercourse with a woman who is suckling a child; but he did not declare them to be prohibited.
Hadith – Bukhari, Narrated ‘Aisha , see also Bukhari 7:745
The Prophet used to like to start from the right side on wearing shoes, combing his hair and cleaning or washing himself and on doing anything else.
Hadith – Bukhari 1:294, Narrated ‘Aisha , see also Bukhari 1:295, 3:362
While in menses, I used to comb the hair of Allah’s Apostle .
Hadith – Abu Dawud, Narrated Abdullah ibn Mughaffal
The Apostle of Allah forbade combing the hair except every second day.
Shaving the Head
Hadith – Bukhari 2:785, Narrated Abdullah ibn Umar
Allah’s Apostle said, “O Allah! Be merciful to those who have their head shaved.” The people said, “O Allah’s Apostle! And (invoke Allah for) those who get their hair cut short.” The Prophet said, “O Allah! Be merciful to those who have their head shaved.” The people said, “O Allah’s Apostle! And those who get their hair cut short.” The Prophet said (the third time), “And to those who get their hair cut short.” Nafi’ said that the Prophet had said once or twice, “O Allah! Be merciful to those who get their head shaved,” and on the fourth time he added, “And to those who have their hair cut short.“
Hadith – Bukhari 2:787, Narrated ‘Abdullah
The Prophet and some of his companions got their heads shaved and some others got their hair cut short. Narrated Muawiya: I cut short the hair of Allah’s Apostle with a long blade.
Hadith – Bukhari 5:504, Narrated Ka’b bin Ujra
We were in the company of Allah’s Apostle at Al-Hudaibiya in the state of Ihram and the pagans did not allow us to proceed (to the Ka’ba). I had thick hair and lice started falling on my face. The Prophet passed by me and said, “Are the lice of your head troubling you?” I replied, “Yes.” The sub-narrator added, “Then the following Divine Verse was revealed: ‘And if anyone of you is ill or has an ailment in his scalp, (necessitating shaving) must pay a ransom (Fida) of either fasting or feeding the poor, Or offering a sacrifice.’ (2.196)”
Hadith – Abu Dawud, Narrated Thawban
Shurayh ibn Ubayd said: Jubayr ibn Nufayr gave me a verdict about the bath because of sexual defilement that Thawban reported to them that they asked the Prophet about it. He (the Prophet ) replied: As regards man, he should undo the hair of his head and wash it until the water should reach the roots of the hair. But there is no harm if the woman does not undo it (her hair) and pour three handfuls of water over her head.
Hadith – Muwatta 51.7
Yahya related to me from Malik from Zayd ibn Aslam that Ata ibn Yasar told him that the Messenger of Allah was in the mosque when a man came in with dishevelled hair and beard. The Messenger of Allah motioned with his hand that he should be sent out to groom his hair and beard. The man did so and then returned. The Messenger of Allah said, “Isn’t this better than that one of you should come with his head dishevelled, as if he were a shaytan?“
Hair Gathered On Top of Head
Hadith – Sahih Muslim, #6840, Narrated Abu Hurayrah
Allah’s Apostle said: There are two types, amongst the denizens of Hell, I have yet not seen them. One possessing whips like the tail of an ox and they flog people with them. (The second one) the women who would be naked in spite of their being dressed, who are seduced (to wrong paths) and seduce others with their hair high like humps. These women would not get into Paradise and they would not perceive the odour of Paradise, although its fragrance can be perceived from such and such distance (from great distance).
Hadith – Abu Dawud, Narrated AbuRafi’
Sa’id ibn AbuSa’id al-Maqburi reported on the authority of his father that he saw AbuRafi’ the freed slave of the Prophet , passing by Hasan ibn Ali (Allah be pleased with them) when he was standing offering his prayer. He had tied the back knot of his hair. AbuRafi’ untied it. Hasan turned to him with anger, AbuRafi’ said to him: Concentrate on your prayer and do not be angry: I heard the Apostle of Allah say: This is the seat of the devil, referring to the back knot of the hair.
Action Items for the uttaqun:
- Do not pluck grey hairs
- Get rid of those braid extensions and hair pieces!
- Clip the moustache and nails, etc, within 40 days
- Women should not put all her hair up on the top of her haid like a camel hump. She may put it up at home as long as some hair lays on her neck still, but not when leaving the house in hijab where the hump can be seen to be under the hijab and drawing attention to her hair.
- While doing salah, a man should not have his hair braided or pulled back in a knot
- Comb your hair from the right side first
- Destroy your clipped nails and hair after cutting it by collecting it and burying it. It is not a sin if you don’t destroy your hair, but it is preferable.
- A woman should not have a hairstyle that resembles a man’s hairstyle.
- Do not imitate the hair styles or colors of the Jews and Christians; do the opposite!
Remember… Allah, subhana watala, sees everything we do!