To access webmail without loggin into your cPanel, follow below simple steps:

1. Open any of your favorite browser.
2. Then go to http://www.your-domain.com/webmail (replace your-domain.com with your actual domain name)
3. Use your complete email address and password to login.
4. Then, you can read your online e-mail using NeoMail, Horde, or SquirrelMail.