We know that there is a shared key in Mountain Lion Safari that allows users to share a webpage with Twitter or an information app, but it doesn't have a default keyboard shortcut. Below we teach you how to set shortcut keys for this operation.
-Open the System Preferences panel, click on the keyboard icon, then the keyboard shortcut tab
-click the app shortcut and click the "+" icon
-Select Safari as the app and enter "Twitter" or "info" as the menu title
-Enter keyboard shortcuts that users want to set up, such as "command-control-t" shortcuts for Twitter, "command-control-m" shortcuts for information
-click Add to start using these shortcut settings.
-Quit Safari and restart. The user clicks the Share button in the toolbar, but where the user's new settings are not displayed, the user can choose File > Share to view.
Once set up, whether you want to share a webpage via Twitter or a message, you can just use the keyboard shortcut.