How to Create a Genesis Theme Template for iThemes Exchange Invoices --- http://amethystwebsitedesign.com/how-to-create-a-genesis-template-for-ithemes-exchange-invoices/

invoice-template.php

<?php
/**
 *
 * Template Name: Exchange Invoice
 *
 *
 * @package Templates
 * @subpackage Exchange Invoice
 * @author  Marcy Diaz, Amethyst Website Design
 * @license GPL-2.0+
 * @link    http://amethystwebsitedesign.com
 */

// Optional Add a custom body class gs-exchange-invoice on single invoice
add_filter( 'body_class', 'gs_invoice_add_body_class' );
function gs_invoice_add_body_class( $classes ) {
   $classes[] = 'gs-exchange-invoice';
   return $classes;
}

// Force full width content layout on single invoice
add_filter( 'genesis_pre_get_option_site_layout', '__genesis_return_full_width_content' );

// Optional remove primary navigation on single invoice
remove_action( 'genesis_after_header', 'genesis_do_nav' );

// Optional remove secondary navigation on single invoice
remove_action( 'genesis_after_header', 'genesis_do_subnav' );

// Remove the breadcrumbs on single invoice
remove_action( 'genesis_before_loop', 'genesis_do_breadcrumbs' );

// Remove post info on single invoice
remove_action( 'genesis_entry_header', 'genesis_post_info', 12 );

// Remove the entry post meta on single invoice
remove_action( 'genesis_entry_footer', 'genesis_post_meta' );

// Optional Remove the author box on single invoice
remove_action( 'genesis_after_entry', 'genesis_do_author_box_single', 8 );

// Remove footer widgets on single invoice
remove_action( 'genesis_before_footer', 'genesis_footer_widget_areas' );

genesis();

style.css

/* iThemes Exchange 
--------------------------------------------- */
.single-it_exchange_prod.full-width-content .entry {
    margin: 0 auto 40px;
    max-width: 960px;
}

.it-exchange-invoice-payment-amount .value,
.it-exchange-invoice-payment-status-block {
    font-size: 24px !important;
}

.it-exchange-invoice-payment-amount,
.it-exchange-invoice-payment-status,
.it-exchange-super-widget .payment-methods-wrapper input[type="submit"] {
    width: 50% !important;
}

/* Optional add new line returns */
.it-exchange-invoice-description-block span.value {
	white-space: pre-line;
}