Three Weeks Before

• Make an invitation list. For a large event party, invite 20 percent more people than you can fit, since typically only 70 percent to 80 percent of invitees attend.
• Decide on a theme, if you want one. Make, buy, or borrow any decorations or music you may need to fit the theme.
• Send invitations. Mail, e-mail, even phone invites are all acceptable.
• Plan the menu. Assemble the recipes (choose only those that can be prepared in advance, perhaps even frozen, with just warming and assembling required on party day). Make a list of how far in advance each can be made, and compile a shopping list. Place an order with your local delicatessen ,bakery or catering agent as needed.
• Line up any help you may need. Consider hiring a high school student or a professional to help with pre- or postparty cleaning or to pass drinks or appetizers, replenish buffet food, tidy up, and generally take some weight off your shoulders.

Two Weeks Before

• Clean any crystal, china, and silverware you’ll be using. And launder and iron linens.
• Come up with a playlist. The music should be upbeat and sufficient to last throughout the party.
• Do a first round of grocery shopping and cooking. Prepare any dishes that can be frozen.

One Week Before

• Clean the house / event location thoroughly. This way, you’ll need only a quick once-over before the party.
• Set the stage. Arrange the furniture as you’ll want it for the party, making sure that guests can move easily from one part of your house /event location  to another. Designate a coffee table or side table for coffee and dessert, if you’ll be serving them. Tuck away things that will be in the way, precious items that might get broken (or even be taken), and any clutter. Figure out the lighting: Using low-wattage bulbs or candlelight will create the right mood.
• Take inventory of cookware and serving dishes. If you don’t have enough for every dish you’re serving, consider purchasing inexpensive pieces from a discount or thrift store. Label each dish with a Post-it so you’ll remember what you plan to use it for at party time.
• Stock the bar. Plan three bottles of wine for every four people, three to four cocktails per guest for a two- to three-hour cocktail party.

Three Days Before

• Notify the neighbors. Let them know you’re having a party if you expect it to be large, loud, or parking-intensive.
• Decorate. Arrange candles, put up theme decorations, etc.
• Check the medicine cabinet. Remove any personal items you wouldn’t want guests to see.
• Set up clean-up stations. Place a box of salt, Wine Away (red wine stain remover), club soda, and a couple of rags in a wicker basket, and store a few in strategic places in case a nasty spill occurs.
• Specify a place for coats. Make space in a closet and fill it with hangers. You could also choose a bed for coats (make sure the room is especially tidy and free of valuables, so you won’t need to worry about them), or purchase an inexpensive portable garment rack.

• Finish grocery shopping. Make a detailed cooking schedule for your remaining dishes. One Day Before

• Set the tables. Or set up the buffet.
• Buy and arrange flowers.
• Finish as much of the cooking as you can /
• Double check with your catering agent Also, for any foods that require cooking on party day, do as much prep (dicing, marinating, rinsing lettuce, etc.) as possible.
• Give your house a once-over. Do whatever touch-ups are needed. Day of the Party

• Finish any last-minute cooking. This should be absolutely minimal!
• Place chairs. Don’t worry about having enough seating for everyone; fewer seats will encourage mingling.
• Display food. One to two hours before guests arrive, set out appetizers and snacks that won’t spoil. Wrap them tightly to ensure freshness; tear off the wrap when the first guest rings the doorbell.
• Greet guests as they arrive. Things should be organized so you’re free to mingle, not tied to the kitchen.