Server permissions issue.

I've purchased a VPS and seem to be running into an issue with my permissions. The server is using cPanel & WHM with CentOS 6.

All of the users on my server (using WordPress) are unable to upload files to their Media Library. They receive the message "The uploaded file could not be moved to wp-content/uploads/2016/04." They are also prompted for the FTP Connection Information when they try to upload or update a plugin.

I have used the chown command to set the owner and group (this will not allow users to create folders or upload/update plugins in Wordpress, but this fixes the WordPress issue):

sudo chown -R usera:usera /home/usera/public_html/ 

I have also tried using the chown command to set the owner and group to nobody (this will not allow users to connect via FTP - they do not have permissions to access public_html):

sudo chown -R nobody:nobody /home/usera/public_html/ 

So my question is, how can I correct the permissions for all the accounts on my server so that they can upload/update plugins in WordPress and connect to FTP?