DNS is a tricky one, isn't it, it can make or break your site and your emails. We try and simplify things as much as we can for our lovely clients, so we have a nifty tool in the platform which will automatically add the correct MX records (these dictate where your emails go) if you're using Google Mail or Office 365 is you're using our nameservers. Nice, eh?
You can get to your DNS records through 'Domains' when you log in to the platform.
Then select Edit under the DNS heading for the domain you want to add your records to.
This will display the full DNS zone that's in place for the domain. In the top section you'll see the option to add MX records for either Google Mail or Office 365. Click on the appropriate button and then click the button in the pop up to set the MX records to Google/Office 365. Job done!