To help my work/life balance, I try only to book meetings and calls on Thursdays and ask people to book in here. To book pick a “service”: either a 30 minute slot or a 60 (actually 50) minute slot. When you do book, I hope that most of the time I will just confirm by Email that that’s fine but occasionally something may have happened and I’ll have to cancel. You should get an Email confirming or cancelling within a day. BEWARE: my diaries are on French time, i.e. CET, Chris Evans time, oops no, Central European time, I think https://www.timeanddate.com/worldclock/?query=paris should show you the time now in CET in case you are uncertain of the time differences and it should allow you to test the time for a future date to make sure no summer time switches affect the time difference.
I have non-interactive online calendar/diary but use that to map my time, put in new online blog posts, work or other, etc. That’s here.