What can I do in this situation

On my dates with my girlfriend we often watch movies or watch tv on the couch or her bed. When we do so she leans against me and I put my arm around her, which is normal right? But when we watch a movie on bed she sometimes acts like she is sleeping and lies down next to/ or behind me. But I don't know what I have to do then (body contact wise)? So normally I just stare at her and wait for her to come back up, because I am too shy to try anything, and know nothing to do in that situation anyways.Any help would be greatly appreciated.

What would you like to do with her? Play with her hair, fondle her body or maybe tickle her if your'e in the mood. She'll tell you if she doesn't like it.
Or do nothing and enjoy the movie with her.

The problem is I wanna do something as reaction to her (like cuddling or something), but I have just no idea what to do. And since this problem is occuring more often I really want some tips/help. Thanks for the response anyway

Try some butterfly kisses on her forehead and see where it goes. All you need to know is when it's time to take a step forward and you have already acknowledged it.

She wants you to pay attention to her body movements. She's laying down because she wants you to lay down. Lay down first, next time, and she will end up laying her head on your chest. Don't be shy, girls love a man who is confident. If she simply lays down beside you, grab her and pull her close to you.