You can watch this instruction video, which gives a good general overview
and specificly shows a lot of options of this online scheduling software.
You should be able to set up your own account quite easily after watching this video.
Is it possible not to use online payments or only cash payments?
Yes, that is perfectly fine.
Payments are only optional.
However, you can save cash amounts in the scheduling overview (below the dollar sign) for your own administration.
