The simplest and best option is to use the import tool located within the Gmail interface. You can find the email and contacts import tool using these steps:
- Login to your Gmail account.
- Click on the Gear icon on the top right-most side of the Gmail interface and then select “Settings”.
- Under Accounts and Import select Import mail and contacts.
- Enter your account email address and then select Continue.
- Follow the steps on the screen.
- Click Start import.
Note: If you have an Apple account, please read the following article.