Go to the post's Attention & Action section, and click Edit.
Messaging: In the Request confirmation section, select from the drop-down one of the options:
Reminder (post to be highlighted in pink)
Attention Requested (post to be highlighted in blue)
Important (post highlighted with orange)
This is the prefix text that will be placed before the post's title. If you select "None", it cancels the feature.
Reminders: Next, select whether you want to send parents reminders until they click the 'Got It' button. Choose 'No' to not send any follow-up reminders.
If you selected "Yes, once a week" or "Yes, twice a week", select the duration for the reminders by selecting the last time a reminder might go out.
Continue making the post as usual.