Speed up Joomla with Cache

IMPORTANT: Go to Entensions > Plugin Manager and make sure the plugin called System – SEF is before the System – Cache in order. If you don’t get the SEF plugin before the Cache plugin, you will get broken images due to an incorrect path.
See this Joomla Forum topic if you have questions: http://forum.joomla.org/viewtopic.php?p=2229886

Clearing / Deleting Joomla Cache

If you need to make changes to your site BEFORE the cache time expires, you must delete the cache before your changes appear on the site.

1. From the Joomla Admin, select Tools > Clean Cache.
2. If you have modified only articles, just select com_content and click Delete.Note: You won’t do any harm be deleting all the cache files.