The 9 Days
The 9 days start Thursday night at 8:58pm.
The restrictions of the three weeks increase from Rosh Chodesh Av (July 16th). The Mishna says in Meseches Taanis (26b) mishenichnas av momaatin b'simcha-when the month of Av comes in, we lessen our simcha.
All restrictions apply on Rosh Chodesh Av as well.
In addition to shaving and music, it is also forbidden to launder clothing (even for use after Tisha B'av). If one has no available clothing he may wash clothing provided that it is not the week of Tisha B'av. If it is the week of Tisha B'av (shavua shechal bo), he should wear dirty clothing (in a year like this, where Tisha B'av falls out on Shabbos and is pushed off to Sunday, Ashkenazim are noheig that the week of Tisha B'av is the whole week before Tisha B'av; Sefardim hold in a year such as this there is no shavua shechal bo).
Freshly laundered is defined as not having been worn since washed.
It is advisable to wear many different items of clothing on the day before the 9 days begin, to ensure that a person has enough clothing during the 9 days.
Freshly laundered clothing may be worn on Shabbos.
Garments worn under the clothing (undershirts, underwear, socks, etc.) may be worn even if freshly laundered.
It is forbidden travel for pleasure, bathe for pleasure/swim, drink wine or eat meat.
One may shower to remove sweat, the water can be warm, but should not be hot (though the Aruch Hashulchan and Rivavos Ephraim imply that the water may be hot). In any case, one should only stay in shower as long as is necessary to remove sweat/grime.
One may not buy clothing, even for after Tisha b'av. One should not renovate their home for decorative purposes (painting, wallpaper etc.).
Gardening is not allowed; it is permitted to cut grass.
Meat may be eaten on Shabbos, even for shaloshudos.
Wine may be drunk on Shabbos. For havdalah, it is preferable to give the wine to a child. If there is no child available, an adult may drink the wine.
Nails should only be cut on Erev Shabbos (a woman who is going to the Mikveh, may also cut her nails during the nine days).