If you no longer need a message, you can delete it by selecting it and clicking . Deleted emails are moved to Trash and then permanently deleted after 30 days.
But with 30 GB of storage or more in your Google Apps account, you don’t need to delete your emails to save space. So, we recommend that you archive them instead.
Archiving removes emails from your inbox to keep it clutter-free. But, the emails stay in your account so you can find them later. It’s like moving emails into a filing cabinet for safekeeping, rather than putting them in a trash can.
See the attachment to this article for instructions.