"Did anyone show you how to operate it?"

Absolutely. I learned everything I needed to know to do a basic calibration with an SPL meter on this forum and in my 1050 manual(it was less than half a page). Read through the walkthrough in the 990 manual as gonk suggested and post any specific questions you still have here. You'll get plenty of help, trust me.

Have confidence; you'll do just fine AND you'll enjoy your system even more.
Tony.