How do I login to my webmail?

Webmail gives you access to your email account anytime, anywhere and without the use of an email client like Outlook. If your domain and hosting is with PlanetHippo then you can access it by visiting your domain and appending /webmail to the end ( https://yourdomain/webmail ). 

If your domain name does not resolve on our servers IP then you would not be able to access it using your domain name. Instead, you would have to use the server "hostname" for example; https://serverhostname/webmail

Your server hostname was sent to you when you signed up with PlanetHippo, and should be available within your cpanel account.