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Adding Categories to a Menu
Click on At Categories drop down tab > choose categories options which you would like to add into menu. Click on Add to menu button to finish.
*Note: Using subcategories instead of making menus at level 2 in Categories when creating multi-level Menus to avoid making an error.
In addition, admins have ability the ability of adding products on Menu items.
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To set featured products to add into Categories, go to Backend of Magento 2 stores > Products > Catalog > click on Edit of chosen products > Mega Menu under Basic SettingMenu.
Adding Custom Link to a Menu
Click on Custom Link drop down > enter Title and add Link into menu. Click on Add to menu button to finish.
Adding Custom Text to a Menu
Click on Custom Text drop down > enter Title and add Content into menu. Click on Add to menu button to finish.
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How to set up Mega Menus
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Allow adding Pages, Categories, Custom Links, Custom Text to Mega Menus.
How to set up Fly out Menus
Admins can set up fly out menus for all levels, click on gearwheel, you will able to set menu mega by choosing no for Is mega menu option. Allow only adding Categories to Fly out Menus.
How to customize Menu Items
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Admins can move positions as well as set up levels of Menus using Down One Up one Under 404 Not FoundMap hyperlink in Move line:
Or implement drag & drop:
*Note: Admins can only implement drag & drop with menus which do not have children.
Adding icon, label into Menu items
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Click on Choose File as below to add Icon for Menus.
Enter Label Name and choose Label color for Label.
- Label color:
Hot: yellow
New: green
Setting up size for Menu items
Allow only setting up size by using marks with menus at level 2 of Mega Menus. 
Deleting a Menu Item
Admins can delete a Menu Item by clicking on remove hyperlink at the bottom of menus.
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