Edit page header on a custom plugin

NOTE

This code will load those scripts on all admin pages. Better you go through the Codex examples to get an idea how you can load the scripts on pages of specific plugins

Here’s the code to load the custom scripts on admin pages

function wpse60745_loadto_admin() {

    // to load styles
    wp_register_style( 'my_plugin_css', plugins_url('plugin-style.css', __FILE__) );
    wp_enqueue_style( 'my_plugin_css' );

    //to load javascripts
    wp_register_script( 'my_plugin_js', plugins_url('plugin.js', __FILE__) );
    wp_enqueue_script( 'my_plugin_js' );
}
add_action('admin_enqueue_scripts', 'wpse60745_loadto_admin');

^{Above code is updated}

Reference

• wp_enqueue_style()
• wp_enque_script()