The functionality to customize the title of a Menu Item is found in App Config/Menu Editor/Menu Editor tab.

1. Click on the Menu Editor tab;

2. Click on the Menu Item for which you wish to customize the title and the Editable and ReadOnly fields for the Menu Item will appear to the right;

3. Enter the custom title for the menu item;

4. Click "Save".  Please note you will be able to see the changes but other users will need to log-out and then back in to view changes.

Starting with the above Menu Item title of "Budgeting Dashboard":

And then changing the CustomText to "Enter Your Budget Here":

The Menu Item title changed as below: