You can add your content to the 3 footer widgets, (leaving the 4th widget area blank of course).
In your style.css file look for the footer-widgets-1, 2 and 3 and you can replace them with the code below, as a start –
.footer-widgets-1 {
float: left;
margin: 0 30px 0 0;
width: 300px;
}
.footer-widgets-2 {
float: left;
margin: 0 30px 0 0;
width: 300px;
}
.footer-widgets-3 {
float: right;
margin: 0;
width: 300px;
}
It should be on or around line 1777 of your style.css file (if you haven’t already made changes to it.)
Let me know if that works