Give each tool its own keyboard shortcut. For example, pressing the V key brings up the Selection tool and pressing the Z key brings up the Zoom tool.
To change the keyboard shortcut for a tool (or to add shortcuts for tools that don’t have any), choose Edit→Keyboard Shortcuts. In the Keyboard Shortcuts dialog box, shown in Figure 19-1, choose Tools from the drop-down menu at the top left of the dialog box (if it’s not already selected), find the tool you want to change (or add) and then highlight the current command. Type a new shortcut and then click OK to make the new shortcut available.
Figure 19-1: The Keyboard Shortcuts dialog box customizes tool commands.