Sometimes you may need to override a particular PHP setting for a single user, such as the memory_limit setting. Unfortunately doing so requires maintaining a separate php.ini for the particular user, but the overall process is relatively easy to execute over SSH.
Assuming we have a cPanel account for example.com, and the username is examplec. Login to SSH and execute the following:
cp /usr/local/lib/php.ini .
echo "suPHP_ConfigPath /home/examplec/php.ini" >> public_html/.htaccess
Be sure to replace examplec with the correct account username.
The account now has its own php.ini allowing you to change most PHP settings; you can either edit it via the customer's FTP account or directly via SSH.