Not sure that it is healthy to have a favorite pile of serger scraps, but if it was, this would be mine:
One thing I did to save time (and money) was to use an e-vite to the party. I've never been a huge fan of them, but am recently converted to Paperless Post. They have a beautiful selection of letterpressed stationery that you can customize and send out digitally. It even comes delivered (to your inbox) in an envelope! How's that for cute.
Paperless Post is not totally free, because you do have to buy "stamps" to send them out, but it is really well-priced. They gave me a bunch of stamps and coins (used for designer cards and special customizations like an envelope liner) just for signing up, so my e-vite for this party was free. Can't beat that! Here's what I chose for the party:
p.s. Paperless Post is not sponsoring this post - I just like them!