Tell them to code-a-long at the top about js-principles-errors-and-stack-traces-readme HOT 1 CLOSED

There are pretty explicit instructions to start coding along halfway through:

Open up index.html in your browser.

NOTE: If you're in the IDE, follow these steps. For local environments, there are a ton of different ways to do this. It will vary based on your operating system, but double clicking on the file in your file system should work on every OS. On macOS, you can type open index.html in the lesson's directory in your terminal. On Linux, the equivalent command is likely xdg-open index.html, and on Windows it should be start index.html.

When the file's open in your browser, open the JS console, and you should see something similar to the following error:

and so on

from js-principles-errors-and-stack-traces-readme.