There are many flexible and convenient ways to backup gmail data.
Below are a few ways which can be considered while backing up the gmail account.
Standalone backup Program
Gmail backup is a simple and easy-to-setup free alternative. Upon installing the program, the credentials need to be typed and it will start downloading all the emails, backing them up securely and allows to restore them.
Third Party Web Service
Backupify is a handy tool that automatically performs scheduled backups for a number of online services. Only the login credentials of the sites that needs backup should be provided and backupify takes care of the rest.
Desktop Mail Client
This is the most common approach and takes just a few minutes to set up. It is a very easy process to set up. After signing into Gmail, click the “gear” in the upper-right corner, choose mail settings, then load the “Forwarding and POP/IMAP”tab. Enable POP for all mail and set Gmail and keep its copy.