It is a Torah obligation for all men and boys over the age of Bar Mitzvah to hear Parshat Zachor. [One who absolutely cannot attend a Minyan should read this passage from a Sefer Torah or Chumash, with the Trop (cantillation) if he knows it.]
Although women are ordinarily exempt from Kriat Hatorah, there is a dispute with regards to Parshat Zachor. Therefore, it is ideal for women to attend Shul. However, a woman who is unable to easily attend Shul (e.g. she is tending to her small children) may instead read this passage from the Chumash.
Ideally, the Ba’al Koreh should be old enough to have a beard. [If this is not possible, a Bar Mitzvah boy should serve as Ba’al Koreh only if puberty is established.]
The Ba’al Koreh should read loudly and clearly, and have in mind to be Motzeh everyone listening to the Kriah. Similarly, all the listeners should have in mind to be Yotzei the Kriah and to fulfil the Mitzvah of remembering to eliminate Amalek.
The word זכר is first read with a Tzeirei - זֵכֶר, and then repeated again with a Segol - זֶכֶר. Some repeat just the word, some repeat the phrase תִּמְחֶה אֶת זֵכֶר עֲמָלֵק whilst others repeat the whole Passuk.
Av Harachamim is recited before Musaf.
