STEP ONE:

Ensure you have downloaded the database file on your system. If you have not, click here download here and choose a version

STEP TWO:

copy the file from your download folder and paste it in the windows folder. This PC > Local Disk(C:) > Windows So the Windows folder should look like this

STEP THREE:

Open the Microsoft SQL Server Management Studio (this could take a few seconds before it comes up)

Connect to the server

Right Click on Databases on the left panel and click on Restore databases.

A new window will open Click on Add

Use the scroll to navigate to the side for more options

Click on the Adventureworks file and then Okay

Click Okay

Click Okay

You should see a successful message been displayed on your screen.

Go to the left panel on your screen and open Databases, You should find the just loaded file in there.