One should endeavor to hear the Megillah as soon as possible. [If circumstances require it to be read beforehand, a Rav should be consulted.] Nevertheless, the Megillah may be read the entire night until (4:51am).
One may not perform any activity that may distract him prior to reading the Megillah. Therefore, one may not eat, drink, nap or perform work from half-hour prior to Tzeit (6:15pm) until after hearing the Megillah. [Nevertheless, if one feels ill or weak, one may eat or drink between Maariv and the Megillah reading. Even so, one should not eat more than a K’beitzah (57 grams) of bread or Mezonot – unless there are health concerns, in which case he should appoint a Shomer (guardian) to remind him to hear the Megillah.]
In many communities an Avel (within 12 months of a parent’s passing or within 30 days of a spouse, child or sibling’s passing) may not serve as Chazzan on Purim, in some communities (including Chabad) an Avel does act as Chazzan on Purim.
The Chazzan recites Kaddish Titkabel immediately after the Amidah. The Megillah is read immediately afterwards.
After the Megillah is concluded, V’atah Kaddosh is recited, followed by the entire Kaddish but without Titkabel.
