When a new case arrives in Salesforce, if the case is assigned to you, the case pops in Service Cloud. You can add or change information about the case, such as the account that the case relates to, the reason for the case, the product that this case relates to, and so on.
To add or change case details, if the case that you want to modify is not already open, open the case. If the case is open in the feed view, switch to the details view. For information on changing the case view, see Viewing case details. Click Edit. The case opens in edit mode. Add information and make changes as required. When you are finished, you can use one of the Save buttons to save the changes. For more information on editing cases, see Salesforce help.