1. Log on to Your cPanel webhosting account
2. Select “MultiPHP INI Editor”
3. Select “Editor Mode”
4. From dropdown, select required domain, to where there is need to apply those changes
5. Add code:

error_log = "/home/npXXXXXXX/logs/teiedomeeninimi_tld.error_log"
log_errors = On

Where “npXXXXXXX” must be changed to Your cPanel account username and “yourdomain_tld” replaced with Your domain name and save changes.
Upon any errors, those are saved to error_log file to Your account home folder under logs folder.