After Maariv of the second night of Pesach we begin to count the Omer. You should count before you say Olaynu. The earlier you count in the evening the more ‘complete’ the counting will be. (ShA1 — MB2)
Women are exempt from this mitzva. It seems that the custom is that women do not count the Omer at all. If they do count, at least they should not say a beracha. (MB3)
If you forget to count at the beginning of the night (tzais hakochavim) you can still count all night long. (ShA1,2)
You can count the Omer in any language that you understand. If you do not understand the language, you are not yotzay even in Lashon Hakodesh. (MB5)
You must be standing from the start of the beracha and throughout the entire sefira. If you sat, you are yotzay. (ShA1 — MB6)
Count the days and count the weeks. If you only count the weeks you are not yotzay. (ShA1 — MB7)
After Sefiras HaOmer, recite ‘Y’hee ratzon…sheyiboneh Bais Hamikdash…’ as a plea to be able to bring the Korban HaOmer. There is also a minhag to say Tehillim 67. (MB10)
If you mistakenly counted Sefira before shkia, count again after dark with a beracha. (ShA2 — MB13)
If you forgot completely to count at night, count during the day without a beracha. The next night you can resume counting with a beracha. (ShA7 — MB34)
If you skipped an entire day, keep counting for the rest of the nights, just without a beracha. (ShA8 — MB35)
If you cannot remember if you skipped a day or not, resume counting with a beracha. (ShA8 — MB38)
What comes first — Sefrias HaOmer or Kiddush Friday night? In shul Kiddush is first. At home, Sefria is first. (ShA9 — MB39)
What comes first — Sefrias HaOmer or Havdalla? Sefrias HaOmer — since the more you delay Havdalla the longer the kedusha stays around. (ShA9 — MB40) What is issur Chodosh? Chodosh is the prohibition of eating from the five grains that took root after the 16th of last Nissan until the beginning of the 18th of Nissan of this year. (ShA10 — MB44)The Shulchan Aruch paskens that Chodosh applies all over the world even nowadays. A baal-nefesh should not rely upon the hetaryim to be lenient. (ShA10 — MB45)
