add mdf to sql server

Follow below steps mentioned:

1. Open SQL Management Studio Express and log in to the server to which you want to attach the database.
2.  In the 'Object Explorer' window, right-click on the 'Databases' folder and select 'Attach...' The 'Attach Databases' window will open.
3. inside that window click 'Add...' and then navigate to your .MDF file and click 'OK'.
4. Click 'OK' once more to finish attaching the database and you are done. 
5. The database should be available for use.

Best Regards,

Suresh Sundar