If you and your provider have a session scheduled today or tomorrow, you will see this session listed under Today's Reminders on the left hand side of the page under your dashboard or in your Upcoming Session List.
To Check-In to a session, click the green Check-In button. You will then be asked to confirm that you are ready to enter the session, and an email notification will send to your provider notifying him or her that you are ready to start the session.
You will then need to click I Agree after reading the Pre-session Agreement. At this point, you will be in the video conferencing page. You must click Start Session to get started. Watch this video for details.