Appointment
Suggest two or three times that would work for you. You will hear back by email whether the appointment is confirmed. Nothing is booked until you get that reply.
Usual hours
Monday to Friday, 09:00 to 12:00 and 14:00 to 18:00, Europe/Zurich.
These are the hours I normally keep, not a live calendar. A time inside them can still be taken, and a time outside them is worth asking for.