The Blessing and the Recitation of the Count
1) It has become customary to recite Leshem Yichud before the counting. Some have written that one should not recite it.
2) In the Leshem Yichud paragraph, there are some who object to mentioning “the Positive Commandment of counting the Omer as it is written in the Torah.” The common custom is to recite this sentence.
3) On the final day of the count there is no need to omit the words “You shall count for yourselves … seven complete weeks … you shall count fifty days.” [Some omit the words.]
4) In some places the Rabbi recites the blessing and the count. In other places the chazzan recites the blessing and the count.
5) The blessing is worded “Who commanded us concerning the count of the Omer.” If one recited “to count the Omer” he need not repeat the blessing.
6) If one counted without a blessing he fulfills the mitzvah, and may not (count again and) make the blessing.
7) Like all blessings of mitzvos, one should stand from the beginning of the blessing. The count should also be made while counting, though if one counted while sitting one fulfills the mitzvah.
8) One who is sick or weak may sit for the counting of the Omer. If one is able to, one should stand for the declaration of the number of days.
9) Each person should count for himself, and a person does not fulfill the obligation by means of the chazzan’s count.
10) If one requested from his fellow to count for him, and subsequently heard his counting, authorities dispute whether he fulfilled his obligation or not. One should therefore not do this. However, one ‘recite’ the blessing by means of hearing somebody else’s blessing, provided that both parties intend the blessing to be effective for both.
11) If one heard the count from another, and both intended the counting to be fulfill the mitzvah for both, the one who heard (but did not speak) the count should count again without a blessing. He may continue to count with a blessing for the remainder of the count. Therefore, one who is ill and cannot count for himself should hear the count from another.
12) A chazzan who needs to count out loud, and forgot to count on one of the days, may not recite a blessing, but should appoint somebody else to recite the blessing out loud. Some have written that he may make an arrangement with one of the congregants to recite the blessing for him, and this arrangement may be relied on under extraneous circumstances.
13) One must count in a language one understands. If one does not understand Lashon Ha-Kodesh, one should read a translation first (and learn the meaning of the words), or count in the language he understands.
14) Some say ba’omer and some say la’omer; both are valid.
15) From the seventh day and on, the number of weeks is also counted. Some say the words la’omer before the number of weeks, and some say the word after the number of weeks.
16) From the eleventh day one recites “today is eleven yom” (not yamim).
17) The number of days of the count must be known before commencing the recitation of the blessing. However, if one recites the blessing with the intention of hearing the number of days from somebody else, he fulfills his obligation (of the blessing), even if he waited for a short period of time between the blessing and the counting.
18) One may not interrupt in the middle of counting the Omer, even for answering Amen.
19) However, if the number of days has already been stated, but not the number of weeks, one may interrupt to respond Amen. Preferably, one should subsequently repeat the number of days.
20) On the week in which a week is completed (7 days, 14 days, and so on), it is possible that one may not interrupt at all.
21) One fulfills the obligation of counting even without reciting a blessing. Therefore, one should beware not to mention the number of days before counting with a blessing. If asked concerning which day it is, one should respond: “Yesterday was such and such.”
22) After the count the prayer for the rebuilding of the Temple is recited. One should focus intensely on the words.
23) Some say a chapter of Psalms (Yechaneinu) after the count, and it should be recited standing. It is also customary to recite Ana Bekoach, and to focus on a different word for the forty nine days of the Omer. Some add a prayer for purity and sanctity.
24) Where Kiddush is recited in shul, the Omer is counted after Kiddush. Where Havdalah is recited, the Omer is counted before Havdalah.