Using Facebook as a Page is a powerful alternative to the traditional login, in that it allows you to comment and post on other business Pages as a Page, rather than as an individual.
To switch to Page mode, simply click on Account in the upper right hand corner and choose “Use Facebook as a Page.” A popup screen will appear; find the Page your want to switch to (probably only one choice in the list); select Switch and you’re off and running. You can also do this by going to your Page and selecting “Use Facebook as <insert Page name here>” on the right hand side.
To switch back to yourself on Facebook, select “Switch back to …” from the dropdown menu under Account in the upper righthand corner. Good luck and enjoy!