functions.php

/**
 * Output the proceed to checkout button.
 *
 * @subpackage	Cart
 */
function woocommerce_button_proceed_to_checkout() {
	$checkout_url = WC()->cart->get_checkout_url();

	?>
	<a href="<?php echo $checkout_url; ?>" class="checkout-button button alt wc-forward"><?php _e( 'Proceed to Checkout', 'woocommerce' ); ?></a>
	<?php
}