Instructions
Launch the CityVille application on Facebook. Wait for your city to load and close any messages that pop up.
Click "Build" in the panel at the bottom of the game. Items you can purchase for your city will be displayed.
Click the "Businesses" icon in the top menu, then click the "Empty Lot."
Place the lot in the location in which you want your friend to open a business.
Click "Share," then click "Share" again. A message that you have a spot open for a business will be posted to your friends' News Feeds.