1. Select the type of control points you want to use. We use cubic (3) control points in this example.
2. Select the background tool.
3. Convert the image to high-contrast black and white.
4. Adjust the contrast so that some grey pixels become black and others become white.
5. Click on the auto-trace button.
6. Hide the background image.
There are also many other settings you can use to fine-tune the result. You might want more details or you
might want less details. Take while to experiment with the settings.