For example, my MC just had an encounter with a jerk. I want him to give her a look that says "Can you believe this guy?" Do I treat the meaning of the look like dialog? Should I use quotes around it? Here is how I handled it:
I think y0u said it well. I'm working hard to avoid too many eye rolls and smiles given they are so easy to overdo. He shook his head, pointed his thumb at [nodded his head toward] the door, and made a face that said, 'Can you believe that guy?' I think if it's not actual dialogue, using single quotes makes that more clear. I'm not positive on that, though. The head nod instead of thumb point is just an option.
I like the way you did it, with the implied dialogue. It makes us readers use our imaginations. I immediately pictured the guy, and what his facial expression was. In fact, as sat here at my computer, I found myself making the 'face' myself! I would caution against using this device too often in one piece, though. It's so effective that people will remember you used it before—and seeing it done over and over could be annoying.
You can also vary it a bit by incorporating the reaction of the recipient of the look into dialogue that prompted th look: Not exactly your scenario, but still an option to keep in mind when there is someone to respond to a subtle or complex nonverbal communication. Let the reaction convey the meaning.