First you need to write your script. In your theme folder create a folder called something like ‘js’. Create a file in that folder for your javascript. E.g. your-script.js. Add your jQuery script to that file (you don’t need <script>
tags in a .js file).
Here is an example of how your jQuery script (in wp-content/themes/your-theme/js/your-scrript.js) might look:
jQuery(document).ready(function($) { $('#nav a').last().addClass('last'); })
Notice that I use jQuery and not $ at the start of the function.
Ok, now open your theme’s functions.php file. You’ll want to use the wp_enqueue_script()
function so that you can add your script whilst also telling WordPress that it relies on jQuery. Here’s how to do that:
add_action( 'wp_enqueue_scripts', 'add_my_script' ); function add_my_script() { wp_enqueue_script( 'your-script', // name your script so that you can attach other scripts and de-register, etc. get_template_directory_uri() . '/js/your-script.js', // this is the location of your script file array('jquery') // this array lists the scripts upon which your script depends ); }
Assuming that your theme has wp_head and wp_footer in the right places, this should work.