On the bottom left of your screen, left-click your connection and click "Open Network and Sharing center". Click on "Change adapter settings" on the top left of the window that opens. You should be looking for whatever active connection you're using. "Local Area Connection" is just the name on the adapter for the tutorial. In Siren's case, it's the one on the far left. Just whichever connection doesn't have a red X.
After that, it should be the same as the tutorial.
Note that if you're giving yourself a static IP address on a laptop, you're going to want to change it back any time you leave the house or connect to another network as it could prevent you from being able to connect to a network with different structure than your own.
