You can modify your sharing preferences for specific upcoming meetings from your Calendar page:
You can only manage sharing for meetings that you choose to add Read to. If "Add Read?" is enabled for a meeting on your calendar, this means that your default sharing and distribution settings will be applied to the meeting. You can change this for specific meetings or a series of recurring meetings by clicking on the "Share" and "Access" buttons on the right side of your Calendar page.
Clicking on these buttons opens up a dialog that looks similar to the share dialog in a meeting report. From here, there are two different tabs you can edit, the Share Report tab, which lets you add specific people to the report, and the Access & Distribution tab, which lets to manage the participant access and distribution settings.
For recurring meetings, after you save a change you'll be give the option to apply that change to all future instances of the meeting or just the one you edited:
Granting direct access to people or teams
On the Share Report tab, you can add specific people, teams, or even your entire workspace as viewers or editors on the upcoming report. To share with a specific person, just type in their email address or name (if they have a Read account). To share with a specific team or your workspace, you can click on the name from the list of suggestions, or you can type the name in the box above. This works just like the Share button in your meeting reports, except that you're setting it in advance, so that it will automatically be shared as soon as the report is available.
Managing participant access and distribution
By default, if you add Read to the meeting then your sharing and distribution settings will be automatically applied to the meeting. If you want to change these settings for a specific meeting, you can do so from the Access & Distribution tab. Here you can choose to set the access level for internal and external participants, between "Editor", "Viewer" and "None".
Please be aware that if other people also add Read to the meeting, they will automatically get editor access and may apply their own sharing settings as well. Therefore just setting internal and external participants to "None" is not enough to guarantee that nobody else will receive access to your report, nor will it prevent you from sharing the report with people directly via the Share Report tab. If you want to guarantee that nobody else has access to the report, you can do this as long as you are the meeting owner, using the "Make report private" option.
Make report private
If you want to ensure that a meeting report is kept private to yourself, you should use the Make report private option:
You can find this setting on the Calendar page by clicking on the Access button for an upcoming meeting that you're the owner of:
If the meeting is part of a recurring series, you'll also be prompted after saving your changes if you want to apply those changes to all future meetings in the series or just that instance.
For more details on how this setting works, see How do I make my meeting reports private?