3) From halachic midday and on, it is forbidden to do most forms of melacha (labor); it is permitted to perform only those melachos that may be performed on Chol Hamoed [Footnote #13: For example, a davar ha-avud (something that will be lost), or a non-professional task that is necessary for Yom Tov]. However, it is customary to permit melacha to be done for a Jew by a non-Jew (Footnote #14: …in contrast to Chol Hamoed, when it is forbidden to have a non-Jew perform melachos for a Jew.).
4) Taking a haircut and cutting one’s nails must be done before midday. If he forgot to do one of these things, he may cut his nails after midday as well, but to take a haircut is forbidden, unless it is given by a non-Jew.
MBY 469 Do not verbally designate meat for Pesach (abridged) (Excerpted from Halachos of Pesach, by Rav Shimon Eider z”l, p. 197):
One should exercise caution not to say (concerning any piece of meat) “This meat is for Pesach.” The reason is that it should not appear as if he is designating it for a Korban Pesach (Pesach offering)! Therefore, one should rather say “this meat is for use on Pesach” or “this meat is for Yom Tov”. There are Poskim who hold that this applies to all types of meat – animals, fowl or even fish. Similarly, one should not say “Here is money; go and buy meat for Pesach.” If, however, one did say, “This meat is for Pesach” or instructed someone to buy meat “for Pesach”, it may, nevertheless, be eaten.
MBY 470:1-3 The fast of the firstborn on erev Pesach (abridged) (Excerpted from The Kleinman Edition – Kitzur Shulchan Aruch, Mesorah Publications, siman 113, pp. 161-162)
6) Firstborn sons, whether a firstborn of his father or firstborn of his mother, fast on Erev Pesach, even when Erev Pesach falls on Friday. (Note: When Erev Pesach falls on Shabbos, the firstborn fast on Thursday.) Even one who was the first to be born after a number of stillborns must fast. (Note: The criterion for fasting as a firstborn is based upon which Egyptians died during the Plague of the Firstborns. Thus any type of firstborn, or one born after a stillborn, or even Kohanim or Leviim are included!) As long as one’s firstborn son is still a minor, the father must fast instead of him. (Note: There are grounds for leniency for one who is suffering a headache or the like or who will have difficulty fasting or eating at the Seder. A Rav should be consulted.) Whether a firstborn (or father of a firstborn) may eat at a mitzvah feast on Erev Pesach depends on the particular custom of each place. (Footnote #24: Nowadays, the custom in many places is that the firstborn eats at a mitzvah feast on Erev Pesach. Common custom is that the firstborns join together and listen to someone - not necessarily himself a firstborn - who concludes a tractate – a ‘siyum’ – and then joins in his siyum meal. After joining a mitzvah meal, the firstborn need not fast the rest of the day.)
7) A firstborn who is fasting on Erev Pesach recites the ‘Aneinu’ (“Answer us!”) prayer during the mincha Shemoneh Esrei prayer. If there are a number (i.e. ten) of (fasting) firstborns praying together in a congregation, a firstborn should not descend before the Ark as the chazzan, since one should not bring oneself to a situation in which one would be required to recite Aneinu in the repetition of the Shemoneh Esrei, which the chazzan recites aloud, being that it is the month of Nissan.
MBY 471:1-3 Not eating any bread (i.e. even matzah) after the 10th hour on erev Pesach (abridged) (Excerpted from The Kleinman Edition – Kitzur Shulchan Aruch, Mesorah Publications, siman 113, pp. 160-161) 5) It is forbidden to eat matzah the entire day of Erev Pesach. Even young boys and girls, as long as they understand the concept of the Exodus from Egypt, it is forbidden to give them matzah to eat on Erev Pesach. However, cooked dishes made from matzah meal may be eaten by any person until the beginning of the tenth hour, that is, until the beginning of the last quarter of the day. From then on, it is forbidden to eat anything except in cases of necessity, when one may eat a small amount of fruit, meat, or fish. However, when eating these things, one must take care not to fill his stomach so that he will be able to eat the matzah that night with appetite.