To access your mailbox with POP3 or IMAP simply configure your email client to use mail.redmail.com as the inbound server

INCOMING MAIL SERVER

IMAP
Host Name mail.redmail.com
Username: youremail@redmail.com
Password: yourpassword

OUTGOING MAIL SERVER

SMTP
Host Name mail.redmail.com
Username: youremail@redmail.com
Password: yourpassword
Use SSL: Yes
Authentication: Password
Server Port: 587

You should enable SSL and/or TLS for security if at all possible