Announcing the death: The Prophet (S) announced the death of Zayd, Ja'far and Abdullah bin Rawahah when they were martyred. The proclamation in a loud voice, in the streets or at the gates of Masajid is prohibited.
Weeping is allowed and wailing is prohibited. Regarding wailing, the Messenger of Allah (S) said:
"I am innocent of those who wail, shave, or tear their clothes (in mourning)" [Bukhari]
As for weeping, there is no harm in it. When the Messenger of Allah's son Ibrahim died, he said:
"Indeed, the eyes shed tears, the heart grieves, but we say nothing but what pleases our Lord. We are sad because of your death, O Ibrahim." [Bukhari]
It is prohibited to dress as a mourner, for more than three days, except in the event of a woman's husband. Then it is obligatory upon her to do so for four months and ten days, as the Prophet (S) said:
"The woman is not to dress as a mourner upon the death of anyone for more than three days, except in the case of the husband. Then she is to do so for four months and ten (days)" [Bukhari and Muslim]
Paying off the deceased's debts: The Messenger of Allah (S) would not pray for the one with debt until his debt was paid off. He (S) said:
"The believer's soul is suspended by its debt until it is rectified." [Bukhari]
Al-Istirja, Supplication and Patience: It is necessary for the family of the deceased to be patient. The Prophet (S) said:
"Patience is only at the initial shock." [Bukhari]
They should increase in supplication and recite the phrase of Al-Istirja which is, "We belong to Allah and to Him we will return." (Inna Lillahi wa inna ilaihi raajioon)
The Prophet (S) said:
"There is no servant who suffers an affliction and says: We are Allah's and to Him we will return. O Allah! Reward me with good in my adversity, and compensate me with better than it," except that Allah rewards him abundantly, and compensates him with what is better." [Muslim]
Washing (ghusl) of the body is obligatory, except in the case of a martyr. If water in unavailable, then Tayammum should be performed.
The spouse is permitted to wash the other. The Messenger of Allah (S) said to Aishah (R)
"If you would pass away, I would wash and shroud you." [Ibn Majah, Ahmad]
The shroud (kafn) is obligatory.
A clean white shroud (kafn) is recommended. The Messenger of Allah (S) said:
"Wear white clothes, since they are the best of your clothes, and shroud your dead with them." [At-Tirmithi]
Silk shrouds are prohibited for men. As for women though permissible are disliked. Abu Bakr (R) said: "The living one is more worthy of new than the dead. The shroud is for the pus and matter that comes out of the deceased.' [Bukhari]
Performing the funeral prayer for the deceased Muslim, like his washing, shrouding and burial is a collective duty. The Prophet (S) said:
"Perform the Salah for your companion." [Bukhari]
Excellence of large number of people participating in the funeral prayer. The Messenger of Allah (S) said:
"If a Muslim dies and forty people, who do not associate anything with Allah in worship, participate in the funeral prayer over him, Allah will accept their intercession for him." [Muslim]
Hastening the burial: The Prophet (S) said:
"Hasten (the burial), if he is righteous, you are hastening him to good. If not, then it is evil you are removing from your necks." [Bukhari]
Following the funeral procession: The Prophet (S) said:
"Visit the sick, and follow the funeral procession; this reminds you of the Hereafter." [Muslim]
The Prophet (S) also said:
"Whoever follows the funeral procession of a Muslim out of faith and hoping for reward (form Allah), then he stays until the funeral prayer and the burial, will return with two Qirats, each of them is as huge as the mount of Uhud. And whoever attends it until the funeral prayer will have a reward equal to one Qirat." [Bukhari]
It is disliked for women to go out to follow the funeral, as Umm Atiyyah (R) said: "We were prohibited from following funeral, but without being strict on us.' [Muslim]
It is disliked to raise the voice while attending the funeral procession with remembrance of Allah (SWT) or recitation. The Companions of the Messenger (R) disliked raising the voice for three things;
(i) The funeral
(ii) The remembrance of Allah (SWT)
(iii) And while fighting. [Ibn Al-Mundhir from Qays bin Ubadah.]
It is also disliked to sit before laying down the body. The Prophet (S) said:
"If you follow the funeral, do not sit till it is placed in the earth." [Bukhari and Muslim]