Click on Settings > Identities, then choose the identity you want to export (usually Default) then click Export on the upper right, then choose a filename. Now on the target PC, go to Settings > Identities, and choose Import then point to the INI file to complete the import process. This will allow you to receive the same permissions settings assigned to you by the server regardless of which PC you're using.
You can also use this method to backup your Unique Identity.
Source - TS3 FAQ