None of the customs of mourning are practiced on Chol HaMo’ed Pesach, because one is commanded to rejoice on these days, as we explained above, in sec. 8, regarding music.
According to some poskim, one may take a haircut on Rosh Chodesh Iyar, because it is like a yom tov (holiday) and none of the customs of mourning apply to it. In practice, though, the custom is not to take haircuts on that day, as the Shulchan Aruch (493:3) rules.
According to Ashkenazi custom, if Rosh Chodesh Iyar falls out on Shabbat, giving it extra joy, one may take a haircut on Friday. One may also get married on that Friday, [shortly] before Shabbat, such that the rejoicing and festive meal take place on Shabbat and Rosh Chodesh. The prevalent custom among Sefardim is to act leniently in this regard only under pressing circumstances.
Yom Ha’atzma’ut is a holiday for thanksgiving and rejoicing. Therefore, it is proper to shave the day before it, and one may even take a haircut. Getting married, however, is forbidden (see below, 4.11).
According to Ashkenazi practice, one may take a haircut and get married on the day of Lag B’Omer, and if needed, one may even act leniently on the night of Lag B’Omer. Sefardi custom, however, forbids haircuts and weddings on Lag B’Omer, as explained above, in sections 3 and 4.
When Lag B’Omer falls out on Friday, even Sefardim are allowed to shave and take haircuts (S.A. 493:2).
According to Ashkenazi practice, one may take a haircut on Friday when Lag B’Omer falls out on Sunday. According to Sefardim, however, this is prohibited (see above, note 8. Regarding weddings: some Ashkenazi poskim rule leniently under pressing circumstances, but Sefardim forbid it; see note 6.)
Even according to the custom of many Ashkenazim, who refrain from making weddings until Rosh Chodesh Sivan, one may get married on the twenty-eighth of Iyar [Yom Yerushalayim]. It is also permissible to organize very joyous events for that day (see below, 4.11).