It is proper just before placing the Tefillin Shel Rosh on the head to look at the letter "Shin" imprinted upon both sides of the box of the Tefillin Shel Rosh. The "Shin" on one side contains four "Zayin’s," whereas the other has three "Zayin’s." There is deep Kabbalistic significance to the seven "Zayin’s" contained in the two "Shin’s" on either side of the Tefillin Shel Rosh, and one should therefore look upon them just before he places the Tefillin upon his head.
The Shulhan Aruch rules that one should leave the Tefillin Shel Rosh exposed, whereas according to Kabbalistic teaching, the Tefillin Shel Rosh should be covered by the Tallit. Our practice follows the ruling of the Shulhan Aruch, requiring that the Tefillin Shel Rosh be exposed.
One should not remove the Tefillin Shel Rosh from the kouracha (Tefillin bag) until after he finishes putting on his Tefillin Shel Yad. Some people mistakenly remove both Tefillin from the bag and then start putting on the Tefillin Shel Yad. This is Halachically improper; one must keep the Tefillin Shel Rosh in the kouracha until he finishes putting on the Tefillin Shel Yad and is ready to put on the Tefillin Shel Rosh. If a person has an attendant helping him, the attendant may take the Tefillin Shel Rosh from the bag to begin preparing it after the individual has placed the Tefillin Shel Yad on the muscle of the upper arm. At that point, his attendant may remove the Shel Rosh from the bag. However, the attendant should not remove the Shel Rosh from the bag before the person has placed the Shel Yad on its proper place on the arm. One must instruct the attendant to wait until this point before removing the Shel Rosh from its bag.
The earliest time when one can fulfill the Misva of Tefillin is the point in the morning known as "Mi’she’yakir." This refers to the point when there is enough daylight to enable one to recognize his friend standing four Amot (approx. 6-8 feet) in front of him. If one has any doubt as to whether or not the time has passed, it is preferable to wait a bit longer to ensure that he does not put on his Tefillin before the time for the Misva has arrived. If one mistakenly put on his Tefillin with a Beracha before the point of "Mi’she’yakir," he does not recite a new Beracha when the time arrives. Of course, he must ensure to be wearing the Tefillin after the point of "Mi’she’yakir."
(Based on Ben Ish Hai, Parashat Vayera)
Summary: It is proper just before placing the Tefillin Shel Rosh on the head to look at the letter "Shin" imprinted upon both sides of the box of the Tefillin Shel Rosh, and to take note of the seven "Zayin’s" contained in the two "Shin’s." It is customary to leave the Tefillin Shel Rosh exposed, rather than covering it with one’s Tallit. One should not remove the Tefillin Shel Rosh from its bag until he finishes putting on the Tefillin Shel Yad. One should not put on Tefillin earlier than the point of "Mi’she’yakir," which means the point when there is enough daylight to enable one to recognize his friend standing four Amot (approx. 6-8 feet) in front of him.
