Wreaths
ETA: I attempted this and they looked AWFUL, so we're not having wreaths.
I made a whole bunch of yellow and white tissue paper flowers, intending to use them in the centerpieces, but I've since found paper flowers that I like more, so instead of wasting all of that effort, I'm going to braid them into wreaths to mark the way to the church like people do with balloons. And our attendants could probably use them to decorate the car or something.
All of the flowers are made up and I've trimmed the edges, so they're finished because I can't puff them up until right before the wedding or they'll get squashed. I also can't braid them til they're puffed up, so that means this project is almost done.