1. With your worktops installed to your design, select Universal Worktops from the Catalogue Items Palette.

2. Filter as Primary Type: Worktops, Secondary Type: Edges
    This will now display the edge options available.

    

3. Select your preferred edge and using the Single Line\Multi-Line Tool in 2020 Fusion up to version 7 or the Freehand Tool from the Insert Tab of your ribbon for version 8 onwards.
Version 7:
How to Use the Single Line Tool in 2020 Fusion
How to Use the Multi Line Tool in 2020 Fusion
Version 8:
Using the Freehand Tool in 2020 Fusion

4. In plan view, click on the Hotspot  to start. Remember to plan in a clockwise direction. Single left click to change direction and double left click to finish.
 You might at this point find it easier to turn off all of your layers except the worktop layer as this will remove the hotspots generated by everything except the worktop.

Before Application of WTEC from Universal Worktops Catalogue
                

After Application of WTEC from Universal Worktops Catalogue