These are the lines of code you need to enable clean url's in Drupal

HTACCESS 3

#This enables the urls to be cleaned
<IfModule mod_rewrite.c>
  RewriteEngine on
  RewriteBase /
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule ^(.*)$ index.php?q=$1 [L,QSA]
</IfModule>

settings.php

/*add the following lines of code at the bottom of the settingps.php to activate clean urls*/

$conf = array(
'clean_url' => 1
);