Depending on how your instructor has configured your Blackboard course, you may see, as soon as you log into your course the announcements page. The announcement icon looks like this.
Announcements will be sorted by date by default. However, your instructor may reorder some particular announcements.
If you are unable to log into your Blackboard course daily, you will want to get in the habit of periodically checking all of the announcements to make sure you have not missed or overlooked something.