To create a mega menu on your website, you have to add Custom Links to your menu. Make sure that you are in the Appearance > Menus tab before you start. Navigate left, where you can see the custom links tab. When you click on it, it will show two fields, type a “#” in the first field and your preferred menu item name in the second field called: Link text. Click Add to Menu.
We type a “#” to make the main link not clickable, you can also type in any URL there.
The new menu item will show up on the right, click it to see more options. The most important thing to check is the Activate Mega Menu option; remember to have it enabled.
When your main menu item is ready we can get to creating the mega menu columns, to do that just add another custom link, again with the “#” as the link and in the link text field type a “–“. Click add to Menu
Drag the created menu item under your previously created main menu item but set it as a subitem. To do that, just move it to the right, just as you would while creating a normal menu.
If you did everything right, the name of the submenu item should change from “–” to “– sub-item“. This is your column. Now you can add your pages under the column, and they will appear on the site under each other.
To create another column, just repeat the last step and set the sub-item under the previous one.