I guess I'm feeling a bit guilty, because when he's asleep I'm usually on my phone or watching TV. I guess I worry all of the TV as background noise is bad, but when he's asleep there's not a lot else I have energy to do!
When he's awake (and not nursing), I talk or sing to him, put him on his playmat or hold him and try to get him to focus on me or on a black and white toy. It's hard because he's so young, and I'm still nervous to take him out on my own.