If I am understanding you right, go to admin, create board and then select a catagory you want the board in, title it and follow the instructions on how you want people to post there.
If it's the other it's this code here:
Place this code in your Main Footer
<table align="center" border="0" width="92%" cellspacing="0" cellpadding="0" class="bordercolor">
<tr>
<td>
<table cellpadding="4" cellspacing="1" border="0" width="100%">
<tr>
<td class="titlebg" align="center" colspan="3">
<font color="000000" size="2">
<b><center><font style="filter:glow(color=white, strength=2); height: 2;">Affiliates</font></center></b>
</font>
</td>
</tr>
<tr>
</td>
<td width="60%" class="windowbg2" valign="top">
<!-- Begin Mini Banners -->
<P>
<marquee height="50" width="500" onmouseover="this.stop()" onmouseout="this.start()" direction="left" scrollamount="3" style="Filter:Alpha(Opacity=100, FinishOpacity=0, Style=1, StartX=0, StartY=40, FinishX=0, FinishY=0);"><font face="verdana" color="#000000">
<center>
<a href="URL OF SITE" Target="_blank">
<img src="URL OF BANNER" width=88 height=31 border=0 alt="BANNER NAME"></a>
</center></font></marquee>
<!-- End Mini Banners -->
</td>
<td width="35%" valign="top" class="windowbg">
<img src="URL OF YOUR BANNER"> <textarea rows="2" name="S1" cols="20">THE HTML CODE FOR YOUR BANNER</textarea></form>
</td>
</tr>
</table>
</td>
</tr>
</table>
Repeat the
<a href="URL OF SITE" Target="_blank">
<img src="URL OF BANNER" width=88 height=31 border=0 alt="BANNER NAME"></a>
as needed for more Banners.