1. You need to open the Developer tab in Excel. You can do this by clicking the File tab and selecting Options >; Customize Ribbon to open the Customize Ribbon Panel, and then select the Developer tab.

2. In the Developer tab, click the VisualBasic button to open the VisualBasic editor.

3. In the VisualBasic editor, select Insert >; User forms or user controls, and create new user forms or controls as needed.

4. After creating a user form or control, you need to double-click the form or control to open the code editor.

5. In the code editor, you can use the menu editor function of VB6 to create a custom menu or menu item. You can use the Menu Editor dialog box to create menu items and set their properties, such as name, visibility, validity and index.

6. After creating a menu item, you can use code to respond to the click event or other actions of the menu item.

7. After creating the menu editor, close the code editor and VisualBasic editor.

8. Return to Excel, click the Developer tab, and then select the menu or control you just created to use the custom menu editor function.