This video shows the stereo disassembly process for the Hyundai Sonata 2011-2013. The vehicle shown is a 2011 Limited with Dimension sound and auto climate controls, other trims will be slightly different but the steps up to pulling the four screws for the actual radio will be almost identical.

YouTube Video

This is the type of panel tool that I use to disassemble the dash

I hope this helps with the process!