打开链接，登录账号，F12，添加代码
<a class="button button--primary button--icon-left button--mw" href="javascript:SWaddToCart(this);"><span class="button-icon button-icon--left fa fa-cart-plus" aria-hidden="true"></span><span class="button-label">Add to Cart</span></a>
点击添加购物车，然后去购物车，添加下面代码
<button class="button button--primary button--icon-left" onclick="apex.submit({request:'CHECKOUT',validate:true});" type="button"><span class="button-icon button-icon--left " aria-hidden="true"></span><span class="button-label">Checkout</span><span class="button-icon button-icon--right " aria-hidden="true"></span></button>
然后点击结算，完结~