You can enable an EIT in SSHR as a separate function without any customization. You can refer further details from http://www.apps2fusion.com/apps-training/apps-functional-documents/ame-sshr/420-hrssa-workflow-employee-self-service
You can use a simple option of adding a button using personalization and calling the function which you have defined which will launch the EIT.
If you want to display the details on the same page then you will have to extend the page by adding a new region on personal information page.
The note you sent seems to be related with workflows (AME) which requires customisation. I have no much knowledge oin it.
I want to make this "US Ethnic Origin" Extra Information to be enable in personal Information (SSHR). Dont know how it can be achievable without any customisation.