I do quite a bit of image resizing as part of my workflow and use the Preview app as my go to application for quick photo resizing. However, in order to bring up the Image Resize window, you need to click Tools on the Menu and then click Adjust Size with my mouse — there is no keyboard shortcut available. Now those of you who have been reading my posts for awhile know that I dislike having to take my hands off of the keyboard, preferring to execute menu commands whenever possible by using keystrokes. So given that there was no keyboard shortcut for the Adjust Size command, I created one.

Below, I’ll outline the process to create a keyboard shortcut to a menu item. You can also use this tip to change existing menu item shortcuts to something that makes more sense for you.

Create a Menu Keyboard Shortcut

Select  > System Preferences from the menu.
Click Keyboard.
Click the Shortcuts tab on top of the window.
If the shortcut is to be used in all applications (such as the Save command), click All Applications in the right pane and then click the + symbol.
If the shortcut is to be used for a specific application that is not already listed in the right pane, click the + symbol. In my case, there was not yet an entry for Preview so I clicked the + symbol in order to choose the application that is to receive the shortcut.
Click the Application drop-down list and choose the application you want to modify. I chose “Preview” from the list.
In the Menu Title box, type in the name of the menu command EXACTLY as it appears on the menu, including any capitalization and the ellipsis (to create an ellipsis, use the Option-Semicolon keyboard shortcut). In my case, I typed in: Adjust Size…
Click in the Keyboard Shortcut box and tap the keys for the shortcut you want to use. In my case, I held down the Control key and then pressed S, which displayed as ^S in the box.
Click *Add. You’re finished! Now enjoy all the extra time you’ll be saving.