Cross-dressing
In our days, many people wear customs in Purim. Obviously there is no Miṣva or Minhag to do this. It is just a popular practice that became accepted in Jewish communities all over the world, especially for children. However we must avoid and warn against cross-dressing in Purim. Wearing clothes specifically designed for the opposite sex is an explicit prohibition of the Tora, Debarim 22:5: "A woman must not wear men's clothing, nor a man shall wear women's clothing, for haShem your God abhors anyone who does this". Therefore, if man dresses to look like a woman, wearing a skirt, or a wig, or using make up, etc., or if a girl dresses to look like a man, they are transgressing a Biblical prohibition. This serious prohibition also applies during Purim, and even when one dresses to look like the other gender 'just for fun' (R Obadia Yosef, Taz, Bach and others) .
Alcohol-consumption
In Purim, Sunday February 24th in the afternoon, we participate in a festival meal or Se'udat Purim. In this banquet we sing songs and express our happiness and thanks to HaShem for our deliverance. It is customary to serve and drink alcohol in this banquet (MT Megila 2:15), but it is NOT permitted to drink in excess. Purim should not be used as an excuse for drunkenness. "In these days," declares Rabbi Weinreb, a leading Orthodox Organization in America "when so many of our young people are prone to experimentation with dangerous substances, it behooves us to warn against the dangers of alcohol, especially on Purim".Quoting from Mishna Berura (sec. 695) on the laws governing the Purim SEUDA, the festive meal, Rabbi Weinreb emphasized that "we are not commanded to become drunk to look foolish and to lose self-control...rather we are commanded to become joyous in a manner that results in love of God and thankfulness for God's miracles."
Please, read THIS very important letter from Rabbi Avraham Nissanian on alcohol consumption and Purim
Tomorrow, Thursday February 21st, is Ta'anit Esther.
In NYC the fast begins at 5:37AM and ends at 5:58 PM