Only Team Admins can Upgrade a Team to Premium.
Upgrading your Team can be done in one of two ways, the first of which can be accessed through Team Settings:
In Team Settings, you can navigate to the Payment tab, where the "Upgrade Now" button can be found:
The second way to upgrade your team can be found on your Team's Projects page:
Clicking on either of the "Upgrade Now" or "Upgrade Team" buttons will take you to a payment window, where you will need to fill in some information. If you have a Promo Code, enter it here. When you are finished, click "Finish Order":
Clicking "Finish Order" will open a small window where you will be asked to enter your credit or debit card information. When you are finished click "Pay". Please only click on "Pay" once:
If your payment was successful, you will see a message reading "You're all set!" like in the image shown below, stating the number of Premium Team Members, as well as the monthly rate for your Premium Team:
To see all benefits of upgrading your Project to Premium, click here.