Adding Custom CSS Classes to WordPress Menu Items
Here’s something that I assumed required a plugin: How can you add one or more CSS classes to a WordPress menu item?
How to Create WordPress Nav Menus: An Introduction
Navigation menus are one of the most obvious features that go into making a site. If you’re building or revising a WordPress theme, you’ll almost certainly have one or more areas where you’ll want users to be able to easily make menus. Fortunately, they’ve thought of that.