As in any good [How To] there should be some specifics in this one too. To not make things confusing between desktops (Desktop Environment or a number of Desktop PCs or the wallpaper space we call desktop) and workspaces (Virtual desktops) - there should be a footnote with those definitions at least, or specify the use case.
The mention of touchpad makes sense for Laptops, but and alternative for Desktop PC users should be provided too, or those that use mouse/touchscreen/etc.
If is about workspaces as shown here:
Then middle mouse button, any touchpad/touchscreen gesture/button that emulates that middle mouse button will reveal the switch and available workspaces list, plus offer the menu to add or remove them one by one, when clicked.
If is not about workspaces - then i’m confused
Anyway, thanks for taking the time to write tutorials!