If you write HTML you can just paste the code below the banner you want to use, in your site.
<a href="http://www.jounin.tk" target="_blank">
<img src="http://www.freewebz.com/jounin/Images/jouninbanner.jpg" alt="JouniN.tk" border="0">
</a>
<a href="http://www.jounin.tk" target="_blank">
<img src="http://www.freewebz.com/jounin/Images/jouninbanner2.jpg" alt="JouniN.tk" border="0">
</a>