// Add the checkout link to the header
add_action('woo_nav_before', 'artificer_header_checkout_link',10);
if ( ! function_exists( 'artificer_header_checkout_link' ) ) {
    function artificer_header_checkout_link() {
    global $woocommerce;
    ?>
    <a href="<?php echo $woocommerce->cart->get_checkout_url()?>" class="checkout"><span class="lozenge"><?php _e('Checkout','woothemes') ?></span></a>
    <?php }
}