There's no easy way to do that. Most of the settings are stored in pref.js but the column layout is stored in the msf files, so these are specific to accounts and not independently portable. There are also some json files that record window states etc. And then there are your extensions that might provide particular features that can't appear unless that addon is installed.

The usual advice is to copy the whole profile and then remove what is not wanted. It's not efficient and there is the small risk, if you're not careful, of leaving behind personal data in removed accounts.