Eve Button is easy to setup, but you should read the Get Started Guide.
Here it is, in PDF form.
Eve Button Quick Start Guide
Visit the Elgato Blog for the latest Elgato Eve information, with many articles and videos about Elgato Eve software and accessories.
Setup Step 1 - Press Eve Button
Press Eve Button once to activate.
Setup Step 2 - Customize Eve Button
Customize Eve Button with the included labels and rubber feet.
Setup Step 3 - Download Elgato Eve App
Download the Elgato Eve app from the App Store.
Search for "Elgato Eve", or use this link:
Elgato Eve app
If you have already set up another accessory, go to Settings in Eve to add Eve Button to your home.