code should by placed in overall header and overall footer page. You can edit them by logging in your forum as a administrator then in administrator CP go to styles and then template and then choose overall header page to edit.
then find these lines
Code:
<a href="{U_SEARCH}" title="{L_SEARCH_ADV_EXPLAIN}">{L_SEARCH_ADV}</a> {S_SEARCH_HIDDEN_FIELDS}
</fieldset>
</form>
</div>
<!-- ENDIF -->
<span class="corners-bottom"><span></span></span></div>
</div>
below this code put
Code:
<div align="center">
</div>
In between of these <div> code place your ad code.
Another place you can place your ad is below navigation bar.
Code:
<li class="icon-logout"><a href="{U_LOGIN_LOGOUT}" title="{L_LOGIN_LOGOUT}" accesskey="x">{L_LOGIN_LOGOUT}</a></li>
<!-- ENDIF -->
</ul>
<span class="corners-bottom"><span></span></span></div>
</div>
Now put:
Code:
<div align="center">
</div>
In between of these <div> code place your ad code.