You can use Quota Modification directly from the WHM to affect on how much disk space an account can use. To alter an account's disk space quota you should do this:

• Login to the WebHost Manager (Use the login information is in your welcome email).
• Click the "Quota Modification" link under the heading "Account Functions".
• Select a domain or a user and click "Modify" button in the bottom of the page.
• Enter the new quota amount in the "Quota" field and click on the "Change" button.

Now you know hot to change the amount of storage space allowed (quota) in a specific hosting account.