1)

In a workflow guide, click the floating plus icon and select "Video Step"

2)

Click on "Screencast"

3)

Click on "Allow"

4)

Once again, click on "Allow"

5)

Select an application window or your entire screen to share with everyone

6)

Click on "Share"

7)

Click on "Stop sharing" when you are done with screen sharing 

8)

Enter title, description and upload a thumbnail if you want, and click "Submit"

9)

Your video is getting uploaded, click on "OK"

10)

Screencast has been added as a step in a Guide