On the fast day of Tisha B'Av, tefillin are not worn in the morning, as tefillin are considered an "adornment", symbols of beauty, which is deemed inappropriate for a day of mourning.
They are worn instead at the afternoon Mincha service.
Some wrap it around the upper arm for less than a full revolution (the bare minimum to keep the knot tight) and then wrap it around the forearm seven times, while others wrap it around the upper arm an additional time before wrapping it around the forearm.
Many Ashkenazim wear the knot to be tightened (not to be confused with the knot on the base which is permanently tied and always worn on the inside, facing the heart) on the inside and wrap inward, while Nusach Sephard Ashkenazim and all Sephardim wear it on the outside and wrap outward.
Rashi held that the passages are placed according to the chronological order as they appear in the Torah: Kadesh Li, Ve-haya Ki Yeviehcha, Shema, Ve-haya Im Shemoa, while according to Rabbeinu Tam, the last two passages are switched around.
An Ashkenazi says two blessings when laying tefillin, the first before he ties the arm-tefillin: ...lehani'ach tefillin ("to bind tefillin"), and the second after placing the head tefillin: ..mitzvat tefillin ("as to the commandment of tefillin"), thereafter he tightens the head straps and says "Baruch Shem Kovod...." ("blessed be the holy name") Sephardim and many members of the Chabad Orthodox movement only recite the blessing on the head-tefillah if they spoke about something not related to tefillin since reciting the blessing on the arm-tefillah.
Although "tefillin" is technically the plural form (the singular being "tefillah"), it is loosely used as a singular as well.