This article discribes how to implement the function to click forward and backward between the pages of a current menu.

Note:
This code does not use to split content to dispose it over an amount of different pages (e.g. the output of a database-query). For this purpose use SmartyPaginate.

Add the following Code to your template:

{load_item_childs id=$MENU->getParentID() assign="sisters"}
{if count($sisters) > 0}
  {foreach from=$sisters item="cur"}
    {if isset($last) && $last->getID() == $MENU->getID()}
      {assign var="next" value="$cur"}
    {/if}
    {if !isset($next) && $cur->getID() != $MENU->getID()}
      {assign var="prev" value=$cur}
    {/if}
    {assign var="last" value=$cur}
  {/foreach}
{/if}

Explanation:
This code figures out, wether the current page has got sister-pages (in other words: whether there are more pages in the current menu), and if, which of them is the previous (“$prev”) and which the next one (“$next”).

Finally the “items”(“$prev” and “$next”) need to be linked:

{if isset($prev) || isset($next)}
  <div>
    {if isset($prev)}
      <a href="{link item=$prev}">previous page</a>
    {/if}
    {if isset($next)}
      <a href="{link item=$next}">next page</a>
    {/if}
  </div>
{/if}

Instead of the words “previous page” and “next page” you may want to use images (e.g. arrows):

<img src="path/to/prev.png">
<img src="path/to/next.png">

The rest will do bigace for you…