Like making bunting. Which, in case you're thinking, "maybe I should do that?!?", is annoying to make and takes a lot of time. Don't do it. At least not for your wedding, if you are doing any other DIY projects. But for a circus themed baby shower, it's fun, livens up a room, and is pretty cheap. (I paid about $10-12 for this, because in the end I bought bias tape instead of making my own. I was tired.) I made one long strand, and then smaller strands for the doorways, the dining room, and the photobooth, so I definitely got good value out of it.
You can also make super fun other things, like cupcake tags. My friend who bakes delicious cupcakes found these on Etsy, but I think they are a cricut or other type of die on toothpicks. This is one of those projects that, for a wedding, would be a huge pain, but for something on a smaller scale, they are adorable, fun, and not terribly time-intensive. And if you're buying them, they are much more affordable if you only need 24 and not 175.
We also got to use our photobooth again. Which yes, we keep set-up in the living room. We're that cool.
So look, your wedding isn't the only party you'll ever get to throw, and the little details get just as appreciated (maybe more) at other parties, they'll be less time-intensive, and you'll actually get to enjoy them. At a wedding, sometimes these projects get swallowed. But our friends walked into the living room and said, "oooh flags!"
If anybody wants a tutorial on how to make bunting, I'll write one up, but there's a lot of them out there. I did use my serger for it, which made it a little faster and the edges were easier to iron.