To enroll in a course, first you have to sign in to your account at lagunita.stanford.edu/login. Then, click the "Find Courses" link at the top of the page.
This will take you to lagunita.stanford.edu/courses, where you can browse all of the current and past courses being offered on the Lagunita platform. Click on the class you want to register for, and you'll end up on the course About page. On this page, click the Register button to register for the class.
And that's it! The course will be added to your Dashboard page at lagunita.stanford.edu/dashboard. Some instructors create a registration confirmation email for their courses, but not all do – so don't worry if you don't get an email right after you enroll.
If the course has already started, you'll see a View Course button next to its name in your Dashboard. Click that button to enter the course. If you don't see a View Course button, your course hasn't started yet. Your instructor will send an email when you can start the course.