May 31, 2012, 8:37 PM — Here's how you can download and use a free app that will show you all of the keyboard shortcuts available for applications in OS X on your Mac.
1. Download the free CheatSheet app.
2. Unzip CheatSheet after your download is finished.
3. Drag and drop CheatSheet into your Applications folder.
4. Double-click CheatSheet to start using it.
5. Launch the application you want to see keyboard shortcuts for.
6. Hold the Command key on your keyboard to see keyboard shortcuts for the app you are currently running.
CheatSheet makes it very easy and fast to use keyboard shortcuts.
For more, see the original article at the link below.