First, you will have to create an account with a @krypt7.com address. After that, just go to the emails tab, then to the settings tab, and start register your domain for outgoing (the messages that you send) & incoming (the messages that you receive) emails.
You must have access to your domain’s DNS records, in order to verify it: just follow the instructions to add the necessary records.
Modification of DNS records can be a scary: if you have any hesitation, contact our support team.
And remember, it may take up to 48 hours for DNS changes to fully propagate.