Wedding decorations have a reputation for being a one day wonder, something you unwrap, use for six hours, and then shove in a bin in the garage forever. I used to think that too, until I kept a few pieces from a friend's backyard ceremony and realized half of it was just good home decor that happened to get dressed up for a party.
The best use for this stuff is anywhere you already gather people. A mantel for a holiday dinner, a long dining table for a baby shower, a covered patio in the spring or early fall when the light is soft and you want the evening to feel a little more done up than usual. Garlands, taper candle sets, good glass vases, runner cloth in a decent weight, all of that moves easily from a wedding into a regular dinner party without looking like leftovers. Spring and early fall are the kind to lean into, since a lot of this is built for mild evenings outside, not for a room that needs to hold up all winter.
Where it falls apart is storage and climate. If you live somewhere small, with no closet or attic to spare, buying a lot of this is just buying clutter with a deadline. Paper and dried flower pieces also do not love humidity or direct sun, they curl, fade, and go brittle faster than you would think, so a sunny windowsill in a hot climate is not where they belong long term.
The difference between a piece that lasts and one that embarrasses you by the third use usually comes down to what is holding it together. Real linen or cotton runners wash and iron fine for years, thin polyester ones go shiny and never sit flat again. Garlands with a wired, finished stem keep their shape when you drape them, the loose, floppy kind sag within a week. Candle holders in solid glass or brass feel like something you would keep in a cabinet on purpose, not something that was clearly bought for one Saturday and forgotten.
It is worth thinking about what it fights with in your own rooms. Heavy gold and crystal pieces look out of place in a plain, modern kitchen. Soft pastel tulle looks strange against dark, moody dining rooms with black trim. If your house already leans simple, keep the decorations simple too.
If I were starting from nothing, I would pick ivory or cream pieces first. They sit easily against almost anything already in a home, and they never look like they were only ever meant for one day.