After creating a new test you’ll come to the point where you have to write your test scenario. To create the step-by-step tasks, you can use the "+ Task Step" button,  which creates ###TASK###, signaling that a new step begins after this. You can also just Copy and Paste it to the locations where you want a new task to start:

You can use the "Preview Test" Button to see how your test scenario will look like for participants using a Desktop or Mobile device: