Before submitting a package for certification, you can either test-sign it yourself by using the SignTool tool, or you can use the Hardware Dev Center dashboard to test-sign the catalog (.cat) files.
To test-sign a package by using the dashboard
Create a cabinet (.cab) file containing the .cat files you want to test-sign.
Sign in to the dashboard with your Microsoft account.
On the left side of the window, click File signing services, and then in the Test-sign (legacy) tile, click Create legacy test-sign submission.
Browse to the .cab file you created, and then click Upload.
Your .cab file will be included in the Legacy test-sign requests list. You can download the signed .cab file when the status has changed to Succeeded.