There are A LOT of commentary nodes scattered around the home. For the easiest time, start a new game then go into modifiers and select:
- All Lights Start On
- Unlock All Doors
- Enable Commentary
You will need to trigger all of the commentary nodes at least once. Interacting with a node will cause it to start and it will immediately count indicated by the "light" going out in the node.
There are a lot of very well hidden nodes, so I recommend that you follow along with this video to make sure that you don't miss any:
If you do miss some and want to take a break, you can "finish" the game and then select "Resume" from the main menu at any time to continue and not lose progress.