The widget was designed to work on mobile and thus has a relatively small size. There are currently 2 ways to use this widget:
using the custom booker-button element to have the widget as a button on your website
using the provided script and having the widget as a button on your website
using the booker-element element and embedding the widget anywhere
All code snippets are found on the configuration page of your widget at Widget Code > Inject Snippet
Button custom element
Place the codesnippet at the end of your body tags of your html. If everything is configured correctly, it wil automatically load.
The widget will then show under a button in the bottom right corner of the web page. There is currently no way of changing the size.
Using the widget inline gives you the option to place the widget anywhere and style its size with CSS as you please. Keep in mind that the widget is designed to work on mobile and thus is visually most appealing in a small screen area.