Where do I find more info?

https://www.cpsc.gov/Business--Manufacturing/Testing-Certification/

When do I test?

If you are required to test, you will do so on the prototype that you will send out to your customers.

If you make a change in your prototype, retest. Color does not constitute a physical change for physical tests, but shape and size can.

How often do I test?

You will need to test yearly. If you are using a supplier's testing reports for a component, request a new document if it is more than 3 years old.

Where do I test?

https://www.cpsc.gov/cgi-bin/labsearch/

Are there exemptions?

Yes, you can find some exemptions for total lead content and flammability testings in the following flow charts from my digital book series.