See the same WAM with the standard, CSS based, GUI.
First, this WAM has been generated in a folder. Put this folder somewhere, it contains all the files for this wam and it is self contained.
Two versions are provided, one with the custom GUI that you designed with the FAUST IDE, and one with a default GUI based on CSS. You can choose the one you prefer to embed in your application. The URI of the WAM is the only thing that changes between the two versions. You can further customize the GUI of the first versions by looking at the Gui/gui.js file and edit the HTML/CSS inside (this file defines the WAM as Web Component).
Here is an example of how to embed this WAM in your application. You can copy/paste this code in your HTML file.