Lucid has an Action available to easily insert the graphical Spinner (spin.js) created by Felix Gnass onto your page. spin.js requires a code import which you can download and install either from http://fgnass.github.com/spin.js/, or have Lucid do this for you by selecting the option from the gear menu on the top left of the Spinner editing window.
Once you have inserted the script header, you can enter various properties into the editing window. If you prefer, you can choose one of the sets of presets from the gear menu, to get you started.
Finally, you need to drag from the little circle on the right of the Spinner action to a div on the page where you want the Spinner to appear.
Note: If you wish to be able to control the Spinner later on from custom code, it's a good idea to use a global variable, or an attribute in the document element, for easy access elsewhere in your code.