Rosh Hashanah is the beginning of the Jewish New Year. As with everything, one must first take into consideration the venue, weather, and your fellow guests. A small dinner at a family member’s house may be more casual than a formal large feast at a restaurant.
Like most events of this nature, we recommend dressing conservatively, respectably, and classy. We'd also advise you to avoid anything flashy. Business or business casual is ideal. If you’re attending a dinner and the host is orthodox, you’re not supposed to wear the color red nor wear leather shoes. If you’re unsure of the host’s beliefs, play it safe by avoiding both. Canvas, cloth, and man-made leather shoes are easy alternatives. Many people will wear white clothing during afternoon ceremonies and choose to keep wearing them through dinner. This is more for Yom Kippur, however. Dark or medium wash denim can be acceptable at some fetes. Be sure to ask the host or check your invitation.
Ladies, a knee length skirt or dress pants with a nice blouse, wrap, or sweater are perfect outfits for this occasion. You also won't go wrong with a little black dress. Keep jewelry to a minimum. Of course, avoid any clothing that is too tight, revealing, or flashy. This is not a time for bedazzled jeans or loud colors! Hair and makeup should also be minimal. The look is clean and understated.
For men, dress slacks in a charcoal gray, light gray, navy, or black with a button-up shirt is a good choice. Perhaps, add a sport coat to be extra chic. This is not an ideal place for printed t-shirts or that old college sweatshirt. You can also wear a nice cashmere or wool sweater, or a polo shirt, with slacks if you’d like. Khaki trousers can be acceptable at some venues. Make sure your hair is groomed and you’ve cleaned under your nails. Cologne should be very light – you don’t want to overpower the room at dinner!
You may want to bring your host a nice bottle of kosher wine, apples to dip in honey (which signifies a sweet New Year), or white flowers as a sign of purity. A hostess gift is a nice way to show your appreciation. Be sure to tell everyone “L’ Shanah Tovah,” which means “to you a good year.”