I'm running Arch Linux on an old laptop (I'm a bit of a noob. Forgive me.) and I set everything up as root. I configured i3 window manager, changed preferences for a bunch of programs, and overall did a bunch of stuff that I should have done as a non-root user as root. How can I best clean up my mess? Is there a way to move my files and configurations over to a different user? If the best way to fix this is re-installing, I'm willing to do it, but I'd like to know if there are any steps I can take to make it easier.
You'll probably be fine, since most of the app specific configuration is written to the user's home folder (/root for root). Create a regular user and give it sudo permissions (or use su and the root password instead), then log in as the new user to make sure everything is fine (it should be). Finally, if you want, you may delete the contents of the /root folder (Make sure not to delete the directory itself though).
You can also try copy some of the settings to the new user's home folder.