How to register and display a custom navigation in WordPress?

Adding a custom navigation to your own WordPress theme is simple.

You do not need any advance skill to do it yourself.

The only pre-requisite to accomplish this is:
1. Know where your functions.php is located.

The functions.php is located in your themes folder inside your WordPress project. And, that is in wp-content/themes/THEMENAME/functions.php.

Step 1: Add function THEMENAME_custom_new_menu() in your functions.php

<?php
function THEMENAME_custom_new_menu() {
     register_nav_menu('primary-menu',__( 'Primary Menu' ));
}
add_action( 'init', 'THEMENAME_custom_new_menu' );

Note: THEMENAME is user-defined. You may change this according to your need.

Step 2: Print your menu anywhere in your theme file (e.g. in your index.php or page.php

<?php
wp_nav_menu( array(
     'theme_location' => 'my-custom-menu',
     'container_class' => 'custom-menu-class' ) );
?>

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