10. Specific Laws Regarding the Mitzva of Sefirat ha-Omer
If, at a time when it is permissible to count, one’s friend asks him, “What is today’s omer count?” one should not answer, “Today is day such-and-such of the omer,” unless he has already counted with a berakha.
8. Counting with a Berakha in Cases of Uncertainty
One who is uncertain whether he neglected to count one day may continue counting with a berakha, because we only defer to the opinion that one cannot continue counting with a berakha when one is certain that he missed a day.
If one regularly prays Ma’ariv at a late hour all year round, it is best that he count after praying at his regular time. However, if one is preoccupied and cannot pray Ma’ariv with a minyan after tzeit, and he intends instead to pray by himself later on, he should preferably count the omer right after tzeit, in order to fulfill the mitzva as soon as possible.
Before counting the omer, one recites the following berakha: “Blessed are you, Lord our God, King of the universe, Who has sanctified us with His mitzvot and commanded us concerning the counting of the omer” Both the berakha and the count are optimally recited while standing, but if one recited them while seated, he has nonetheless fulfilled his obligation .