Personal Gmail Accounts
Head on over to your Gmail inbox as you normally would (Gmail.com), click the gear icon in the top right corner. If the update is available for your account, you will see an option that reads “Try the new Gmail”. Click it!
G Suite Accounts
The second way to get the new Gmail is to have your system admin enable it on your G Suite account at work or school. Administrators should be able to access this as part of their Early Adopter Program by going to the Admin Console and selecting to allow users to access the new Gmail.
If you’re not a regular Gmail
After the admin has turned this on, individual accounts will receive the “Try the new Gmail” option on their accounts under the Settings route, just like personal accounts. It may take some time for the option to appear.
If you’ve tried out the new Gmail but can’t get used to it yet and would rather switch back, you can head back to the gear icon to revert to the Classic Gmail.