There is no obligation to recite Hallel on Purim. One reason for this is that the reading of the Megila, which tells the story of the miraculous events, takes the place of Hallel. Therefore, if one cannot hear the Megila, there are Poskim who hold that he should recite the complete Hallel. This should be done without a Beracha, as there is a difference of opinion on the matter.
After the Shir Shel Yom (Psalm of the Day), the Mizmor (Tehilim 22) "Al Ayelet HaShachar" is added. Esther was referred to as "Ayelet Hashachar," and this was the prayer she offered upon approaching the King’s private chamber.
It is prohibited to eat even a small amount before hearing the Megila on Purim morning, even if one has already prayed. Therefore, one should insure that his wife and children hear the Megila promptly, so that they can eat.
Immediately after Shacharit, the Matanot LaEvyonim are distributed. Performing this Misva early is not only a fulfillment of "Zerizim Makdimim L’Misvot," but it also enables the recipients to use the money to buy what they lack for the holiday.
The Shulhan Aruch rules that the Beracha of Shehechiyanu is not recited before reading the Megila in the morning. This applies even if one did not fulfill the Misva of Megila the previous night.
The Hida (Rav Haim Yosef David Azulai, 1724-1807, Lev David, Ch. 30) brings a custom for both men and women to light two candles in honor of Mordechai and Esther on Purim. After lighting the candles, one should give Sedaka and offer heartfelt prayers and requests in their merit.
There is a widespread custom to don costumes on Purim. The Hida mentions this specifically with regard to the Seudah. The Rama even permits men to dress up in women’s clothing. He argues that since it is in the Purim spirit, it does not constitute a violation of the Torah prohibition of cross-dressing. Nevertheless, Hacham Ovadia and Hacham ben Sion both rule that one should not rely on the Rama’s leniency. Although Hacham ben Sion does permit children to wear the other gender’s clothes, Hacham Ovadia was opposed even to that.
The Ben Ish Hai (Rav Yosef Haim of Baghdad, 1833-1909, Ateret Tifferet) brings a custom for women to adorn themselves with their fanciest jewelry, even more than Shabbat and Yom Tov. This custom has its origins in the Kabbalah. This should only be done within the confines of her own home and not to go out publicly, so as not to breach the standards of modesty.
