Proper manners of dressing:

Men should not wear silk or gold:

The Prophet (peace be upon him) said:

“Do not wear silk (clothes), for whoever wears (them) in this life will be deprived of them in the Hereafter.”
(Reported by Al-Bukhari and Muslim)

The Prophet (peace be upon him) said:

“Silk (clothes) are worn only by him who has no share in the Hereafter.” (Al-Bukhari and Muslim)

The Prophet (peace be upon him) said:

“Wearing of silk and gold has been made unlawful for males and lawful for the females of my nation.”
(Reported by At-Tirmidhi)

Modesty in clothing:

The Prophet (peace be upon him) said:

“Whoever allows his lower garment to drag out of vanity, Allah will not look at him on the Day of Resurrection.”
(Reported by Al-Bukhari and Muslim)

The Prophet (peace be upon him) said:

“On the Day of Resurrection, Allah will not look at him who trails his lower garment out of pride.”
(Reported by Al-Bukhari and Muslim)

The Prophet (peace be upon him) said:

“What is below the ankles of a lower garment is condemned to the Fire (Hell).” (Reported by Al-Bukhari)

It should be noted that it is only men who are forbidden to let their dress drag, which is not the case with women.

The Messenger of Allah (peace be upon him) said:

“Allah loves to see the sign of His Bounties on his slave.”
(Reported by At-Tirmidhi)

Modesty of women:

Allah says:

]قُل لِّلْمُؤْمِنِينَ يَغُضُّوا مِنْ أَبْصَارِهِمْ وَيَحْفَظُوا فُرُوجَهُمْ ذَلِكَ أَزْكَى لَهُمْ إِنَّ اللَّهَ خَبِيرٌ بِمَا يَصْنَعُونَ. وَقُل لِّلْمُؤْمِنَاتِ يَغْضُضْنَ مِنْ أَبْصَارِهِنَّ وَيَحْفَظْنَ فُرُوجَهُنَّ وَلا يُبْدِينَ زِينَتَهُنَّ إِلا مَا ظَهَرَ مِنْهَا وَلْيَضْرِبْنَ بِخُمُرِهِنَّ عَلَى جُيُوبِهِنَّ وَلا يُبْدِينَ زِينَتَهُنَّ إِلا لِبُعُولَتِهِنَّ أَوْ آبَائِهِنَّ أَوْ آبَاء بُعُولَتِهِنَّ أَوْ أَبْنَائِهِنَّ أَوْ أَبْنَاء بُعُولَتِهِنَّ أَوْ إِخْوَانِهِنَّ أَوْ بَنِي إِخْوَانِهِنَّ أَوْ بَنِي أَخَوَاتِهِنَّ أَوْ نِسَائِهِنَّ أَوْ مَا مَلَكَتْ أَيْمَانُهُنَّ أَوِ التَّابِعِينَ غَيْرِ أُوْلِي الإِرْبَةِ مِنَ الرِّجَالِ أَوِ الطِّفْلِ الَّذِينَ لَمْ يَظْهَرُوا عَلَى عَوْرَاتِ النِّسَاء[
(النور: 30-31)

This means: “Tell the believing men to lower their gaze (from looking at forbidden things), and protect their private parts (from illegal sexual acts, etc.). That is purer for them. Verily, Allah is All-Aware of what they do. And tell the believing women to lower their gaze (from looking at forbidden things), and protect their private parts (from illegal sexual acts, etc.) and not to show off their adornment except only that which is apparent (like palms of hands and face), or outer dress like veil, gloves, head-cover, apron, etc.), and to draw their veils all over Juyubihinna (i.e. their bodies, faces, necks and bosoms, etc.) and not to reveal their adornment except to their husbands, their fathers, their husband's fathers, their sons, their husband's sons, their brothers or their brother's sons, or their sister's sons, or their (Muslim) women (i.e. their sisters in Islam), or the (female) slaves whom their right hands possess, or old male servants who lack vigor, or small children who have no sense of the shame of sex.” (24, An-Nur: 30 - 31)

Allah says:

]وَقَرْنَ فِي بُيُوتِكُنَّ وَلا تَبَرَّجْنَ تَبَرُّجَ الْجَاهِلِيَّةِ الأُولَى[
(الأحزاب: 33)

This means: “And stay in your houses, and do not display yourselves like that of the times of ignorance.” (33, Al-Ahzab: 33)

Allah says:

]وَالْقَوَاعِدُ مِنَ النِّسَاء اللاتِي لا يَرْجُونَ نِكَاحًا فَلَيْسَ عَلَيْهِنَّ جُنَاحٌ أَن يَضَعْنَ ثِيَابَهُنَّ غَيْرَ مُتَبَرِّجَاتٍ بِزِينَةٍ وَأَن يَسْتَعْفِفْنَ خَيْرٌ لَّهُنَّ وَاللَّهُ سَمِيعٌ عَلِيمٌ[ (النور: 60)

This means: “And as for women past child-bearing who do not expect wed-lock, it is no sin on them if they discard their (outer) clothing in such a way as not to show their adornment. But to refrain (i.e. not to discard their outer clothing) is better for them. And Allah is All-Hearer, All-Knower.”  (24, An-Nur: 60)

Allah says:

]يَا أَيُّهَا النَّبِيُّ قُل لأَزْوَاجِكَ وَبَنَاتِكَ وَنِسَاء الْمُؤْمِنِينَ يُدْنِينَ عَلَيْهِنَّ مِن جَلابِيبِهِنَّ ذَلِكَ أَدْنَى أَن يُعْرَفْنَ فَلا يُؤْذَيْنَ وَكَانَ اللَّهُ غَفُورًا رَّحِيمًا[
(الأحزاب: 59)

This means: “O Prophet! Tell your wives and your daughters and the women of the believers to draw their cloaks (veils) all over their bodies (i.e. screen themselves completely except the eyes or one eye to see the way). That will be better, that they should be known (as free respectable women) so as not to be annoyed. And Allah is Ever Oft­Forgiving, Most Merciful.” (33, Al-Ahzab: 59)

`A’ishah (may Allah be pleased with her) narrated:

“May Allah have mercy on the early immigrant women. When the part of verse:[ وَلْيَضْرِبْنَ بِخُمُرِهِنَّ عَلَى جُيُوبِهِنَّ ], (meaning: “And to draw their veils all over Juyubihinna (i.e. their bodies, faces, necks, and bossms, etc).” was revealed, they tore their thick outer garments and made veils from them.”
(Reported by Abu Dawud)

Umm Salamah (may Allah be pleased with her) narrated:

“When the part of verse: [ يُدْنِينَ عَلَيْهِنَّ مِن جَلابِيبِهِنَّ ], (meaning: to draw their cloaks (veils) all over their bodies (i.e. screen themselves completely)." was revealed, the women of Ansar came out as if they had crows over their heads by wearing outer garments.” (Reported by Abu Dawud)

The Prophet (peace be upon him) said:

“O Asma’, when a woman reaches the age of menstruation, it does not suit her that she displays her parts of body except this and this, and he pointed to hes face and hands.” (Reported by Abu Dawud)

Women should not overdo their perfume:

The Prophet (peace be upon him) said:

“The prayer of a woman who uses perfume for this mosque is not accepted until she returns and takes a bath like that of sexual defilement (perfectly).” (Reported by Abu Dawud)

The Prophet (peace be upon him) said:

“If a woman fumigates herself with perfume, she must not attend the Evening prayer with us.”
(Reported by Muslim)

Men emulating women
and women emulating men:

Ibn `Abbas (may Allah be pleased with him) narrated:

“The Messenger of Allah (peace be upon him) had cursed the males who emulate females. He cursed the females who emulate males.” (Reported by Al-Bukhari)

Abu Hurayrah (may Allah be pleased with him) narrated:

“The Messenger of Allah (peace be upon him) cursed the man who puts on the dress of a woman and the woman who puts on the dress of a man.”
(Reported by Abu Dawud)

Ibn `Abbas (may Allah be pleased with him) narrated:

“The Messenger of Allah (peace be upon him) cursed effeminate males and masculine females.”
(Reported by Al-Bukhari)

Cleanliness and the traits of instinct:

Good manners of cleanness:

[see the selected quotations in: Lessons 31-34]

The traits of instinct:

The Prophet (peace be upon him) said:

“There are five acts which are quite akin to the Fitrah (traits of instict): Circumcision, shaving the pubes, trimming the nails, plucking the hair under the armpit and clipping (or trimming till one’s skin is about to appear) the moustache.”
(Reported by Al-Bukhari and Muslim)

The Prophet (peace be upon him) said:

“Do the opposite of what the pagans do. Keep the beards and cut the moustaches short.”
(Reported by Al-Bukhari and Muslim)

`A’ishah (may Allah be pleased with her) narrated:

“Allah's Messenger used to let his head in (the house) while he was in the mosque and I would comb his hair. When in I`tikaf, he used not to enter the house except for a need.” (Reported by Al-Bukhari)

Umm `Atiyyah Al-Ansariyyah narrated:

“(There was) a woman (who) used to perform circumcision in Madinah. The Prophet (peace be upon him) said to her: Do not cut severely as that is better for a woman and more desirable for a husband.”
(Reported by Abu Dawud)