Import Data button not on custom entity ribbon

I'm new to data importing.  I've been exporting data from one Solution, then exporting from the destination entity on another Solution and copying and pasting the data between spreadsheets.

Now it's time to get smarter.  I looked up how to create a data map and found an instruction to navigate to the entity and click the Data Import button; however, on my custom entity there is no Data Import button.  And from the Data Maps view (Settings>Data Management), there is no way to create a new one.

I appreciate some guidance.  I'm sure there's a better way that copying and pasting data!  ;-)

CRM Online 2016