Praise be to Allah.
The Hadith states what a mourning widow is prohibited from doing and what she is requested to do.
First, she must remain in her house in which she was living when her husband died. She remains therein until her iddah (mourning period) comes to an end. This is four months and ten days. Unless she is pregnant, wherein her mourning period ends when she gives birth. Allah says in the Quran,
"For those who are pregnant, their waiting period is until they deliver" (al-Talaq 4).
She does not leave the house except due to need or necessity, such as visiting the hospital due to illness, buying what she is in need of from the market, such as food or other items, if she cannot find others to do such for her. Similarly, if the house is destroyed, she leaves it for another house. Finally, if she does not find anyone who she knows close to her and she fears for her safety, she may move due to that need.
Second, she may not wear any kind of beautiful clothing, either yellow, green or other. She must wear clothing which is not beautiful or attractive, regardless of whether it be black, green or otherwise. The important aspect is that it is not beautiful or attractive. This is what the Prophet (peace be upon him) ordered.
Third, she must not wear jewelry, either gold, silver, diamonds, pearls or anything of that nature. This is regardless if it be bracelets, chains or rings. She may not wear anything of this nature until her mourning period is over.
Fourth, she must refrain from using perfume. She cannot perfume herself with either incense or any other kind of items that make the body smell good. The only exception to this is when she cleanses herself after her period. In that case, there is no harm if she applies some kind of incense.
Fifth, she should not apply kohl. She can neither use kohl nor anything similar to kohl which is a beautification for the face, a beautification that may be considered something that attracts people. As for the normal beautification of using water and soap, there is nothing wrong with that. But the kohl which is a beautification of the eyes and other similar items that woman put on their faces are not to be used.
These are the five items that a woman must attend to when her husband dies.
However, there are many other acts that the general masses believe or have fabricated concerning a mourning woman. For example, they say that she cannot talk to anyone, she may not talk on the phone, she can only take a shower once a week, she cannot walk barefoot in her house, she cannot go out under the light of the moon, and other superstitions that are simply false. There is no basis for any of these. She may walk barefoot or with shoes in her house. She fulfills her needs in the house, such as cooking her food and the food of her guests. She may go out in the light of the moon on her roof 1 or in her garden. She may wash herself whenever she wishes. She may speak to anyone she wishes as long as it is not suspicious speech. She may shake hands with women and men she is related to-- as for those men she is not related to, she may not shake their hands. She may remove her head scarf if she is not in the presence of men she is not related to.
However, she should not use henna or saffron either on her clothing or in her coffee. This is because saffron is a kind of perfume and it is not allowed for her to perfume herself. She cannot be proposed to. One may indirectly make a statement intent to her but a clear proposal is not allowed.