To make a shared Google Calendar, here are the steps:

1. Go to Google Calendar on your computer (calendar.google.com) and sign in.
2. On the left side, find the section called "Other calendars." Click the plus (+) icon next to it and select "Create new calendar."
3. Give your new calendar a name, add an optional description, and choose the time zone. Then click "Create calendar."
4. Once created, find your new calendar under "My calendars" on the left. Click the three dots next to its name and choose "Settings and sharing."
5. Scroll to the "Share with specific people" section and click "Add people or groups."
6. Enter the email addresses of the people you want to share the calendar with. Choose their permission level (e.g., see all event details, make changes to events, or manage sharing).
7. Click "Send" to invite them. They will get an email to accept and add the shared calendar to their accounts.

This calendar will now be visible and editable by everyone you shared it with, depending on the permissions you set.