With Announcement Templates, you are able to design custom header and footers that can be easily applied to any of your Announcements. To start, go to Administration > Header/Footer Templates.
From this screen, click on Default Template to see what your Default Announcement Template will look like.
You can choose to edit your default template, or you can click Add New Template so that announcement creators will have additional template options to choose from. For each template, you are able to edit the Header (where it says "Type here..." and the Footer (the box with your school name and address) sections of the template. Your Announcement content will fit right in the middle. Once you’re happy with how it looks, hit Preview if you’d like to see what it will look like in an inbox. If you’re totally happy with it, go ahead and hit Save.
Check out this article to see how to use your template once you've created it!