1. Create a custom config file. It depends on which UI you are using on where it is located. If you are using the Standard UI, it is under Tools:Customize. Pick Setup, type in a name in the "Save In" box, and save. If you are using the Themes UI, it is under Tools:Workspace:Customize. Type in a name in the "Save In" box, and save.
2. Go to your User Data folder, and make a backup all the files with the name you gave to your custom config file. There may be one or two.. depending on which UI you are using.
3. Go to your Data folder, and backup the tcw18_xml.ini file, and the Desktop18.ist file.
Put these in a safe place.