In most word processors it is possible to assign keyboard shortcuts to the various functions of the Zotero word processor plugin toolbar (i.e. add citation, edit citation etc.). How to do this depends on your word processor.

1. Click the Office Symbol at the top right of the program.
2. Click “Word Options.”
3. Select the “Customize Tab.”
4. Click the “Customize” button at the bottom of the window next to “Keyboard Shortcuts.”
5. Select the “Macros” category in the box on the left.
6. Locate the Zotero items in the box on the right and select one to assign a keyboard shortcut.
7. If it already has a shortcut it will show in the “Current Keys” box.
8. To assign one, place the cursor in the “Press new shortcut key” field.
9. Press the keyboard combination you want to assign, e.g. when assigning a combination to add a new Zotero citation, press ctrl-alt-A
10. If the “Currently assigned to” field says “[unassigned]”, you can use this shortcut without any conflicts with other commands.
11. Repeat the process for the other Zotero commands.

See this blog post for longer, illustrated instructions.

1. Open Tools → Customize keyboard…
2. Select the “Macros” category in the box on the left.
3. Locate the Zotero items in the box on the right and select one to assign a keyboard shortcut.
4. Press the keyboard combination you want to assign, e.g. when assigning a combination to add a new Zotero citation, press ctrl-option-A
5. If it already has a shortcut it will show in the “Current Keys” box.
6. If the “Currently assigned to” field says “[unassigned]”, you can use this shortcut without any conflicts with other commands.
7. Repeat the process for the other Zotero commands.

See here for more details.

1. Open Tools → Customize…
2. Click on the key to you want to use, from the list of assignable keys in the top portion of the dialog.
3. Find the appropriate Zotero macro in the bottom part of the dialog. The macros are in LibreOffice Macros → user → Zotero → Zotero. Click on the desired action in the list (probably ZoteroAddCitation)
4. Click the “Modify” button.
5. Click “OK” and enjoy!

The keyboard shortcuts for the plugin actions are shown in the AppleScript menu. They use the Control and Option keys.

The Shortcuts of the AppleScript Menu are handled in the filenames of the scripts. To change them go there via:

Script-Menu (where the Zotero Menu is located in the Menu Bar at the top of the screen) → About this Menu → Open Folder

Or by path there, which is: '/Users/yourusername/Library/Application Support/Microsoft/Office/Word Script Menu Items'

You can there see the Keyboard Shortcut after the Backslash.

c stands for Control, m for command, s for shift and o for Option

At least one of c (Control) and m (Command) must be included and s (Shift) and o (Option) are optional. So a sample name for assigning the 'Add Citation' to CMD+A is: 'Add Citation\ma.scpt'

This will also update the Menu entry to the new shortcuts.

See here for more details.