Account Administration
If you have the correct roles within your account, there is a menu option to under Settings > Account Settings.
Within each account you have access to (& the appropriate permissions), you can administer the following:
Account Information:
Account Name - this is what is displayed in the account picker and is also referenced in any notification emails that may be received.
Account Image - this is what appears in the left hand sidebar for this account (this overrides the Org level icon / image)
Membership:
Invite new users
Manage existing users - including:
Updating their roles within the account (see: Roles & Permissions | Explore for information on Roles & their permissions)
Removing them from the account
If you are part of more than one account, you can choose from a list of those accounts, no matter which account you are currently using.
You can also choose to leave the account in the “Your Accounts” screen / main account settings screen.