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 meeting? will be shown for editing the settings of your choice.
The timeslots can be adjusted by selecting “Advanced user-defined timeslots” (if not already specified for this meeting), then selecting the “Edit Timeslots” link that appears; timeslots can be combined, removed, or added.
In a recurring meeting, you can choose to limit the change by selecting “Modify current only” or to modify all of the sessions in the rest of the series by selecting “Modify all future recurring meetings.” After modifying a meeting, you may elect to send e-mail notification to participants via the checkbox above the timeslot table.
Click Publish Modification when you are finished making changes.