Once a test is scheduled, it will show up on the home screen of the student, see https://help.sowiso.com/en/articles/5127040-taking-a-test
If you want to experience this yourself, you can use the Student settings to override the general availability and start date (and even the number of attempts) to make the test available to yourself. Here's how: https://help.sowiso.com/en/articles/3876398-test-settings-for-individual-students
Now, you can take the test in the same way that students will.