After you sign up to Particle's Web Development Environment, follow these four easy steps.
Go to build.particle.io and click on Create New App, you'll see this:
Add the Carloop library to your app by clicking on the Libraries button and search for the Carloop library. Once you find it, click on it.
To include the Carloop library in your app, you have to manually click the INCLUDE IN APP button so the app you are building will now which library to use.
Now you are ready to start programming your own app! Follow Hello World on the next page to learn how to blink and LED!