Isn't it just the hardest? After I work really hard with plot hooks and maps and encounter design, now I have to decide what color the carpet is?

But it's kind of important. I dumped my players in a really cool puzzle dungeon, but they just got confused, because it was a series of similar-shaped symmetrical rooms. I needed to put some landmarks in those rooms to orient them. I ended up improv-ing the room contents, but it turned out pretty bad, because I would forget my own descriptions of what was in the rooms. And they were kind of non-memorable. "Uh, there's a desk." "What's in the desk?" "A piece of paper in the company letterhead." "What's on it?" "It's blank." "Oooooh."

Actually, that part turned out pretty fun. I might bring that paper back someday with a secret message.

One thing that does help me a little is the newer/modern map-making software like Dungeon Draft (+ additional mods with more items). They are all limited in terms of what graphic assets exist to put things into a room... but, when you have the items available on a side bar, and you are looking at that empty room, scrolling through them can help you figure out "what belongs in this space." As a result, I think my dungeons may be better "dressed" than they would without that.

I still don't do as great a job as I could with sounds, smells, etc, though. I tend to be visual in both design and description.