You are right in creating a test site and doing a test upgrade there first to work out the kinks and create a new style. But then you want to turn off your live site, upload the files for the site, point to the current database (that you have done a new backup of) and then run the install/upgrade.php script on the live (turned off) database. Then export/import your new style to the live site and any modifications and test it and turn it back on.
|