If your Internet Service Provider (ISP) has migrated some of your Google data over, you most likely already have your email, mail folders, contacts, and calendars already in your account. To migrate other types of data, we recommend using Google Takeout, a project by the Google Data Liberation Front that allows users of Google products, such as YouTube and Gmail, to export their data to a downloadable ZIP file.
To do this, make sure you are logged into your Google Account and then go to: https://www.google.com/settings/takeout.
After you have downloaded all of your data, items from Google Drive and Google Photos, for instance, can be uploaded to your portal through the Documents section on the web.
Contacts can be imported into the Contacts section.
Email can be migrated via the IMAP protocol. See this article for more information.