Hello lipking39

                           You can enable bridge mode on SBG10 when you need to connect separate router to the modem to access Wi-Fi because when enabling bridge mode the Wi-Fi on SBG10 will be disabled so you can access internet only through direct connection. To setup bridge mode you need to follow the steps mentioned on the link below,

                               http://arris.force.com/consumers/articles/General_FAQs/SBG10-Bridge-Mode-Setup

Let us know if this helps