50 minutes with 10 minutes between hours.

I hope I can explain this.
I have tried to set up appointments for my patients in 50 min intervals, however I need 10 minutes between patients to prepare myself and the room for the next patient.
However my calendar schedule does not allow for that and just shows continuous 50 minute increments with no breaks.

This is what I would like to achieve:

1) Booking is in 60 minute intervals on the hour.
2) The "confirmation"/Duration actually shows 50 minutes of treatment time starting on the hour.

Thanks in advance for any help you can give me.