When you first log in to the system, you'll probably want to import your current active listings into Bridge Listing Input. To do that, look for the Import Listing link on the right-hand side of the Dashboard. Clicking this link will open a dialog that allows you to search for active listings in your connected MLSs by listing number. You only need to enter the listing number; Bridge Listing Input will search across all of your connected MLSs for that number and return any matching results.
Pick a listing from the results shown and that listing will be imported into the system. From there, you'll be able to edit the listing and publish it to any of your connected MLSs and broker systems. Keep in mind that you'll want to carefully review the listing input form if you plan on republishing the listing to multiple MLSs or brokers, as the import may not have contained all of the data necessary for successful publication to those systems.