ExpiresActive On
ExpiresByType text/html "access plus 1 month"
ExpiresByType text/css "access plus 6 month"
ExpiresByType text/javascript "access plus 6 month"
ExpiresByType image/gif "access plus 6 month"
ExpiresByType image/jpeg "access plus 6 month"
ExpiresByType image/png "access plus 6 month"

<Files ~ "\.(js|css|gif|jpe?g|png)$">
 Header append Cache-Control "public"
</Files>