Tired of clicking the green button to increase the size of the current window? Set a keyboard shortcut for that instead! You’ll be making your own keyboard shortcut for this one since it isn’t set by default, but what a handy keystroke it becomes once you configure it:
- Go to System Preferences and “Keyboard”
- Choose “Keyboard Shortcuts”, then go to “Application Shortcuts” and click + to create a new shortcut
- Enter “Zoom” into the “Menu Title” section and then click into the Keyboard Shortcut box to define your keyboard shortcut (Control+Command+= is set in the example)
Now you can hit Control+Command+= (or whatever else) to instantly zoom and maximize the current window, nice!
http://osxdaily.com/2013/03/22/5-simple-window-management-keyboard-shortcuts-to- improve-workflow-in-mac-os-x/