Microsoft SQL Server Management Studio is available for free from Microsoft and can be downloaded through this link: https://msdn.microsoft.com/en-us/library/mt238290.aspx
Once downloaded, Install and open MSSQL Management Studio from the Start menu.
Connect to the server, provide the required credentials.

STEP-02
Choose your database name from the list you have created from the Websitepanel control panel. Here it is showing as "test"

STEP-03
Right-Click on the Database name "test" and Click "Tasks". Click "Restore", then click "Database"

STEP-04
Choose "Device", then click "..."

STEP-05
Select the Backup Devices.

STEP-06
Find the Backup database from the folder.

STEP-07
Click on OK.

STEP-08
Restore the Database

STEP-09
Choose "Options" and "Restore Options".
Tick the "Overwrite the existing database 9WITH REPLACE)"

STEP-10
Restored successfully!

STEP-11
Delete the Database existing user.

STEP-12
Delete the object

STEP-13
How to connect to User mapping

STEP-14

STEP-15

DONE!