Tutorial: How to clear Magento cache

This tutorial will show you how to clear and disable Magento cache. You should keep cache disabled while editing the Magento core or template files

1. Open Magento admin panel

2. Go to System>Cache Management

3. Check all Cache types and in the Actions box select refresh

4. Then select all Cache types and in the Actions box select disable

5. Also click Flush Magento Cache and Flush Cache Storage buttons

Now you are free to perform any changes to the template files.

(click to enlarge)

Source: http://www.templatemonster.com/help/how-to-clear-magento-cache.html