If you follow our party planning checklist, we promise you won't be vacuuming the living room and defrosting appetizers as the first guests arrive.

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So, you're hosting a 40th birthday bash ... or a bridal shower ... or an anniversary party for your parents. It isn't a huge, life-changing event like a wedding, where you'd have to start planning a year ahead of time and work with multiple vendors -- and lose your mind -- to make everything note-perfect. This party will probably be a pretty DIY affair: It'll be held at your home, with homemade food, and you're not expecting an enormous crowd.

But it's not a toddler's birthday, either -- it's a grownup party, and to get it right, you'll be doing a fair amount of planning. So, where (and when) do you start? When do you shop and cook? How much wine should you buy? And -- perhaps most importantly -- how do you avoid the dreaded scenario of opening the door to your first guests while still in your robe and slippers?

This handy-dandy checklist will erase a lot of the stress from the party-planning process. If you follow these simple steps, we promise you won't be scrambling to vacuum the living room and defrost appetizers as the doorbell rings. You'll be able to mix, mingle and enjoy your festive creation.

We'll start about a month before party day. The first thing you should do is...