You can update your password from your account settings.
Note: Unless you are the account owner, you can only edit your own password. To update the password for another team member, you'll need to be logged in as the account owner.
Update your own password
Select Settings from the menu on the left, open My Profile, and go to the Password & security tab.
Enter a new password in the space provided, then click Save. You can now log in with your updated password.
Update a team member's password
As the account owner, go to Settings > Team Members and open the team member you want to update. Enter a new password for them and save.
If you would like to send the new password to the team member, check the box that says Email to user. They will receive an email with the updated password they can use to log in.