1. Open the inbox. In Global Navigation, click the Inbox icon. If the Inbox icon includes a numbered indicator, the indicator shows how many unread messages you have in your Inbox. Once you read the new messages, the indicator will disappear.
2. Using the Inbox. The inbox is organized into two main panels. On the left  is the conversation panel. Here, you can see your messages listed with short previews. On the right  is the reading panel, where you can read a selected message. You can use the top navigation bar  to filter which courses you see messages from, or to change from the default inbox view to view unread or sent messages. To send a new message, you need to click the Compose icon  near the right-center of the navigation bar.
3. Setting up your message. After you have clicked the Compose icon, you will see a new message window pop up. Use the drop down menu to choose the course you want to send a message about . Then click on the Address Book icon  and select Teachers  to find the instructor for that course.
4. Writing your message. Add your subject text and message text in the appropriate boxes . If you wish to attach a file or video, click the icons in the lower left corner . When you finish your message, you can click the Send button , or alternatively, you can cancel your message by pressing the Cancel button (or the “x” in the top right corner.)
For more information, including advanced message options, please see the following guides from Instructure: