How to arrange sub-forums into 3 columns
Aranjare subforumuri in 3 coloane
 
AdminCP > Look & Feel > (choose skin) > ipb_styles.css

add to the last line of CSS:
table.ipb_table ol.subforums1 {margin-top: 3px;float: left;width: 33%;}table.ipb_table ol.subforums1 li{background: url('{style_images_url}/subforum_nonew.png') no-repeat 0 50%;padding: 0 15px 0 15px;margin: 0;float: left;}table.ipb_table .subforums1 li.unread { font-weight: bold; background-image: url('{style_images_url}/subforum_new.png'); }table.ipb_table ol.subforums2 {width: 33%;overflow: hidden;}table.ipb_table ol.subforums2 li {background: url('{style_images_url}/subforum_nonew.png') no-repeat 0 50%;padding: 0 15px 0 15px;margin: 0;float: left;}table.ipb_table .subforums2 li.unread { font-weight: bold; background-image: url('{style_images_url}/subforum_new.png'); }table.ipb_table ol.subforums3 {width: 33%;overflow: hidden;}table.ipb_table ol.subforums3 li {background: url('{style_images_url}/subforum_nonew.png') no-repeat 0 50%;padding: 0 15px 0 15px;margin: 0;float: left;}table.ipb_table .subforums3 li.unread { font-weight: bold; background-image: url('{style_images_url}/subforum_new.png'); }
AdminCP > Look & Feel > (choose skin) > Board Index > boardIndexTemplate

find:
<ol class='ipsList_inline ipsType_small subforums' id='subforums_{$forum_data['id']}'> <foreach loop="subforums:$forum_data['subforums'] as $__id => $__data">     <if test="showSubForumsLit:|:$__data[3]"><li class='unread'><else /><li></if> <a href="{parse url="showforum={$__data[0]}" seotitle="{$__data[2]}" template="showforum" base="public"}" title='{$__data[1]}'>{$__data[1]}</a><if test="isNotLast:|: empty($__data[4] )">,</if>     </li>     </foreach> </ol>
replace with:
<ol class='ipsList_inline ipsType_small subforums2' id='subforums_{$forum_data['id']}'>     <foreach loop="subforums:$forum_data['subforums'] as $__id => $__data"></ol>         <ol class='ipsList_inline ipsType_small subforums3' id='subforums_{$forum_data['id']}'>             <if test="showSubForumsLit:|:$__data[3]">         <li class='unread'>         <else />     <li>         </if>         </foreach>         </ol>         <ol class='ipsList_inline ipsType_small subforums' id='subforums_{$forum_data['id']}'>     <foreach loop="subforums:$forum_data['subforums'] as $__id => $__data">     </ol>         <ol class='ipsList_inline ipsType_small subforums1' id='subforums_{$forum_data['id']}'>         <if test="showSubForumsLit:|:$__data[3]">         <li class='unread'>         <else />         <li>         </if>             <a href="{parse url="showforum={$__data[0]}" seotitle="{$__data[2]}" template="showforum" base="public"}" title='{$thislangwords['go_to_forum']}'>{$__data[1]}</a>     </li>     </foreach>             </ol>
same to
AdminCP > Look & Feel > (choose skin) > Forum View > forumIndexTemplate