Yesterday, I got an Evite in my email from my sister, Mary Clayton, who is hosting her 3rd annual Christmas Party (this party is mostly for her friends, co-workers, and a select few family members, i.e. me and not our parents

). Each year, there is a different theme, and I always look forward to it, as it's high-lar-i-ous.

Here is the text from this year's invitation (with just a weeee bit of tweaking to make it appropriate for this family board - it IS an adults only party after all!):
Twas four nights before Christmas...and it was time to DRINK SOME BEER AND EAT SOME COOKIEEEEEEES!!!! Friday, December 21st, 9:00 pm, Clayton's House! Don we now....the ugliest Christmas/snowflake patterned/Norwegian reindeer nightmare sweater you can dig out of your Salvation Army donation pile. We're serious. There will be a contest. Those without sweaters will be banished to the smoking patio, and it's gonna be cold. Rules: 1. You must wear a hideous sweater for the ENTIRE night unless some sort of strip tease is involved. 2. You must not pee on the bathroom floor. (We know who you are!) 3. You must not bring mistletoe and pull it out of your pocket at opportune moments; that's gross. 4. You must wear your dancin' shoes or none at all. It's a Holiday Hootenanny! Activities: 1. Aforementioned Ugly Sweater Contest 2. DJ Drew B will be Drewin' it up in Amanda's old bedroom so that you may rock around the Christmas tree if you so desire 3. Christmas Carol-oke (no musical talent required) 4. Grillz Contest (optional) - You may purchase grillz at your local Kangaroo gas station or you may make your own. There will be a contest if enough of you little sugar plum fairies participate. 5. Drinking - beverage selection may include spiked hot apple cider, spiked hot chocolate, spiked egg nog, Amanda's ubiquitous Jell-O shots (now in festive holiday colors!) and WHATEVER YOU BRING (hint hint). 6. Refreshments - nothing says Christmas like love handles, so there will be party trays from Chick-fil-a, as well as Little Debbie Christmas Tree cakes, fresh out of the plastic wrappers. The piece de resistance will be a gingerbread-person decorating station; however, for every cookie decorated, one must be made in the likeness of the hostess. Tip: flattery will get you everywhere; non-attractive cookies will get you no more cookies.
How fun does this sound?
And where can I find an ugly sweater? I looked at some last night at Wal-Mart, and they are kind of expensive (well, expensive considering I will only wear it once unless there is another ugly sweater contest in my future). I can hardly sew a button on, so making something may be out of my range. I don't want to just participate - I want to WIN!
Also, any help with a creative response is welcome.

With Evites, you can post a comment with your RSVP. For example, one already posted is: "Oh the weather outside is frightful and so is this sweater I'm about to rock!" Ideas?