A transfer switch is wired directly into your home's electrical panel, so this is not a DIY disconnect. Hire a licensed electrician, and your only hands-on job is protecting the unit safely in transit.
Pro tip: Photograph every wire and breaker label before disconnection; a clear photo set makes the electrician's reinstall faster and safer.
Watch out: Never disconnect or reinstall a transfer switch yourself; it is wired into the main panel at line voltage and mistakes are lethal or start fires.