96:7 When filling the cup for havdalah, one should fill it completely until a little runs over; doing so is a sign of blessing. (One shouldn’t overflow it too much, as that would be wasteful – Mishnah Brurah 296:5.) One takes the cup in his right hand and the spices in his left hand and holds them like that until he recites the bracha of hagafen over the wine. He then switches the cup to his left hand and picks up the spices in his right to recite the bracha of Borei minei besamim over the spices. (As a general rule, whatever one is reciting a bracha over should be in one’s right hand – MB 296:29.) He then recites the bracha over the candle, after which he again takes the cup in his right hand and he recites the bracha of haMavdil. (The cup is never placed down because all the brachos should be recited over a cup – MB 296:30.) He then sits and drinks the whole cup by himself. (There is a difference of opinion as to whether havdalah should be recited sitting or standing – OC and Rema 296:6. In either case, one should drink while seated – MB 296:6. If one drinks less than a cheekful, he does not fulfill his obligation in havdalah – MB 296:9.) The small amount of wine that remains in the cup is poured out and the candle is doused in it. One also puts drops of the remaining wine in the corners of his eyes as a sign of affection for the mitzvah. The practice is for women not to drink from the havdalah cup.
96:8 One should put a little musk in the spices because the bracha we recite is that G-d "creates various types of spices." It's also good to take myrtle; since one mitzvah was already performed with it, we can perform another mitzvah with it.