704. Celebrating Rosh Chodesh
97:2 It's a mitzvah to increase the amount of food at one's Rosh Chodesh meal. (Doing this by day is sufficient; one need not do so also by night - Mishnah Brurah 419:2.) If Rosh Chodesh falls on Shabbos, one should cook one dish more than he normally does for Shabbos. (One need not have bread at his Rosh Chodesh meal but it is meritorious to do so - MB 419:1.)
97:3 One is permitted to work on Rosh Chodesh. Women are accustomed not to work on Rosh Chodesh. This is a good custom and it should not be treated lightly. (If men do this, it is no custom at all - MB 417:2. There are different opinions as to how women should act when Rosh Chodesh is two days long - MB 417:4.)