Quote - I forgot how to smart prop...sob!

bob1965 said most of it, but there is one more point to be aware of.

Quote - Save the prop to the props folder and answer "yes" when Poser asks if you want to save as a smart prop.

You will only be asked if you want to save as a smart prop when saving a single prop. If you use "Select Subset" to include two, or more, props in one pp2 (as you probably would with earrings), you won't have the option to save as a smart prop, and you will be forced to go the route of editing the resulting pp2, as explained by bob1965.