You still do that this way, it's just that your physical button will be for the device plugged into it rather than the TV itself. Instead of turning on the TV w

You still do that this way, it's just that your physical button will be for the device plugged into it rather than the TV itself. Instead of turning on the TV with a physical button, you'll turn on your Chromecast, Apple TV, Roku, Blu-Ray player or whatever you have plugged in. That device will then turn on the TV using HDMI.