I linked some of my old outfits on my user page, but I noticed that they're set to private. I can't find anything that lets me change the public/private setting. How do I change this? Thank you.

Yeah, the Public/Private toggle was removed from the wardrobe outfits at some point during a fix or upgrade. People have been asking for it to come back, but it hasn't yet. Until it comes back, I don't think you can do anything to change already existing avatars.

There's some talk about it here, Set saved outfits private / public by default, so you might want to keep an eye on that to see if there's ever any staff update or reply.

[edit] You can try on the outfit then re-save it as a new "public" avatar.

Well, that explains why I can't find the option. There is no option! I'll try saving them as new sets. Thanks!