If you create a meeting without the Calendar tool on the site, but add the Calendar tool later, you can add each meeting individually to the Calendar.
Select the Sign-Up tool from the Tool Menu of your site.
To change any of the initial settings of the meeting, use the Modify option shown at the top of Meeting Details.
The information described in How do I create a meetings? will be shown for editing the settings of your choice.
Select the check box next to Yes, publish the meeting to the Calendar tool.