Access the Customize dialog box by selecting the View | Toolbars | Customize menu option, and select the Keyboard tab.
Select the command that you want to modify by using the Category and Menu Selection lists. Once you have selected a command in the Commands list, the current shortcut key(s), if any are assigned to that command, will be displayed in the Current Shortcuts box.
Highlight the command for which you will assign new shortcut keys.
Click in the New Shortcut box.
Type the keys you want to assign to this command. The keys you pressed appear as you type them.
Click the Assign button, and the new shortcut keys appear in the Current Shortcuts box with any other shortcut keys currently assigned to the command.
Click Apply to accept your changes.
As in the other tabs, you can use the Create button to first create a command and tie it to a custom program. You can then click User Defined from the Menu Selection list to select this command. All user-defined commands appear in the Commands list.