To make changes, LOG IN (see below), then click on the + in the lower right of the calendar,
then click on a day and add or modify an event on that day.

Login by typing igorspectre (or your own Google login) in the email box, then typing the password in the password box in the upper right.

Once you're logged in, the calendar will appear.
(So if you see a calendar above, you're logged in.)

OR you can set up your own new Google account to access the calendar, but email igorspectre@gmail.com with the Gmail address you'd like to use so we can invite you.