how to get the currency selector to show on the UI?

I installed the free theme, setup two currencies (USD as the default). I checked every page of the site, but there is no option to switch between the two currencies – its fixed as USD for the entire site. How do actually get the currency switcher onto a page?

I checked individudal product pages, as well as cart, checkout, home page, category pages etc. No sign of it.

I went through all available options in the admin UI for the plugin, but could not find anything to “enable” it.

Any ideas?