To create a transparent folder on your home screen, follow these steps:

1. Create a folder using the usual method such as drag an app onto another app.
2. Tap open the folder and then the grey button.
   
3. Select the colorful button on the right.
   
4. Here, drag the Opacity slider all the way to the left, and tap Done.
   
5. Now, you’ll get a transparent folder.

Video tutorial: