WordPress.org

You can either install it automatically from the WordPress admin, or do it manually:

1. Unzip the archive and put the wp-pagenavi folder into your plugins folder (/wp-content/plugins/).
2. Activate the plugin from the Plugins menu.

Usage

1. Open wp-content/themes/your-theme-name/footer.php
2. Add anywhere: <?php wp_pagenavi(); ?>
3. Go to WP-Admin -> Settings -> PageNavi to configure WP-PageNavi.

Changing the CSS

If you need to configure the CSS style of WP-PageNavi, you can copy the pagenavi-css.css file from the plugin directory to your theme's directory and make your modifications there. This way, you won't lose your changes when you update the plugin.

Alternatively, you can uncheck the "Use pagenavi.css?" option from the settings page and add the styles to your theme's style.css file directly.