I gave you the CSS code to add already (note that the URL of the image will have to change based on the image name you want to use and where you uploaded it on your website):
.hikashop_checkout_address_left_part .button{
color: white;
background-image: url(../images/button_blue_shape2.png);
background-repeat: no-repeat;
background-position: right;
background-color: transparent;
padding-right: 10px;
padding-left: 5px;
padding-top: 2px;
padding-bottom: 2px;
}
and told you that you need to add it in the front end CSS file that you can edit in the Display tab of the configuration of HikaShop. That's all there is to it.
