Is the Shofar Kosher?
One must verify that the Shofar is Halachicly valid. This means that:
- It must be purchased under a reliable Hashgacha to verify it comes from a valid animal.
- One must check that it does not contain cracks or holes that can invalidate it.
See Chapter 1 for the full details of these laws.
How to hold the Shofar:
The Shofar needs to be placed on ones lips when he blows. If feasible, it is proper to blow the Shofar from the right side of one’s mouth. It is proper to position the mouth of the Shofar facing upwards as opposed to having its mouth point towards the side. See Chapter 2 Halacha 10 for the full details of this subject!
How many sounds must one blow?
Initially one is to blow 30 blows Tashrat 3x, Tarat 3x and Tashat 3x for each and every group of individuals. If one is unable to do so then some Rabbanim permit one to blow Tashrat three times having in mind by the Shevarim Teruah that whichever is not correct is considered like the voice of an animal, not being done for the sake of a Mitzvah. See Chapter 3 Halacha 1 for the full details of this subject!
How long is each sound to be?
The Tekiah of Tashrat is to be at least 18 Terumatin long. The Tekiah of Tashat and Tarat is to be at least nine Terumatin long. Each Shever is to be exactly three Terumatin long. One is to blow at least nine Terumatin in the Teruah. One may lengthen the Tekiah as much as he desires. One may blow as many Terumatin as he desires within the Teruah blow. One is not to blow more than three Shevarim although some are accustomed to add a small sound after the three Shevarim and so is the Chabad custom. See Chapter 3 Halacha 7 for the full details of this subject!
Who says the Bracha on Mivtzaim?
Blowing for other men: One who has already heard Shofar, or plans to fulfill the Mitzvah with a later blowing, should have the listener say the blessing. If however the listener is a man and is unable to say the blessings himself then one may say both blessings for him. [On the second day men of Sefardic origin do not say the Shehechiyanu blessing.]
Blowing for only Women: If one is blowing for only women, [then if the women are of Ashkenazi custom], she is allowed to say the blessings herself. If she cannot say the blessing herself one may not say the blessings for her. [If she follows the Sefaradi custom then she is not to make the blessing at all.]
See Chapter 2 Halacha 9 for the full details of this subject!
It is important to remind those hearing Shofar to have in mind to fulfill the Mitzvah of Shofar, as Mitzvahs require Kavana. See Chapter 2 Halacha 3 for the full details of this subject!
When may the Shofar be blown:
The Mitzvah to blow Shofar begins from sunrise of each day of Rosh Hashanah until nightfall [צאת הכוכבים]. If one blew before this time but after the beginning of dawn he does not need to blow again. See Chapter 2 Halacha 4 for the full details of this subject!
May one blow past sunset?
One may blow without a blessing from after sunset until nightfall. See Chapter 2 Halacha 4 for the full details of this subject!
Blowing without a Minyan:
If one is blowing Shofar on Rosh Hashanah without a Minyan in order to fulfill the Mitzvah, he is to beware to delay the blowing of the Shofar until three hours have passed from the beginning of the day. [If however he will not be able to blow at a later time then certainly he is to do so even within the first three hours!] See Chapter 2 Halacha 15 for the full details of this subject!
 Sefer Haminhagim: The Baal Tokeia is to review the Mamar, and this is of course in addition to being expert in the laws of blowing.
 As is the simple implication of the ruling of the Gemara Rosh Hashanah 34b, and Michaber/Admur in 590/1-2 that the 30 blows are Biblically required due to doubt as what consists of a Teruah, and so rules Ramban in Milchamos Hashem. However there are opinions in the Rishonim [Rosh/Chinuch/Ran] which bring Rav Haiy Gaon which rules that in truth only 9 blows are needed and there is no doubt at all, as all the sounds of the Teruah are valid.
 The length of the blows is measured by the amount of Terumatin [טרומטין] worth they contain. טרומטין refers to a short blow similar to that contained in the Teruah. [i.e. Tu, Tu, Tu = three טרומטין]. Thus if one were to say that a Tekiah must contain 10 Terumatin this would mean that the length of the Tekiah must be long enough for one to blow 10 Terumatin within that amount of time. So if it takes five seconds to blow 10 Terumatin the Tekiah would have to be five seconds long.
 Admur 588/1; Chayeh Adam 141/1; Mishneh Berurah 588/1; Kaf Hachaim 588/2