Configuring Magento for Development / Debug Mode

1. Disable Cache 
System > Cache Management > Select All [check-boxes] > Actions = Disable > Submit

 

2. Re-Index All 
System > Index Management > Select All [check-boxes] > Actions = Reindex Data > Submit

 

3. Disable Compilation 
System > Tools > Compilation > Disable

Note : By default compilation mode is disabled. So just check if the Compiler Status is Enabled or not.

 

4. Turn on Error Reporting 
a> Open index.php and un-comment the following line

Php代码  

1. #ini_set('display_errors', 1);  

 

b> Open .htaccess and add the following line at the end

C代码  

1. SetEnv MAGE_IS_DEVELOPER_MODE "true"  

 

5. Turn on Logging 
System > Configuration > Advanced > Developer > Log Settings > Enabled => Yes

 

6. Configuring Mangeto Error Page 
rename errors/local.xml.sample to errors/local.xml

 

7. Install ‘Easy Template Path Hints’ 
Install Easy Template Path Hints for turning on/off the template path hints for frontend and backend easily & securely.

 

That’s all. Let me know for any missing points.
Happy Debugging!

 

来源：http://www.blog.magepsycho.com/configuring-magento-for-development-debug-mode/