Sometimes when i stop girls that are walking during the short convo they eventually interrupt by saying i "i have to go" or continue walking while i'm talking to them. When they do this what should i say/do?

I always carry some kind of large net

nothing, they are not interested.
when a girl walks away from me, I just stand there and look at "the camera" (I imagine there is a camera there filming all this and I look at the camera like "WTF just happened?") I learned this from some pick up guy on youtube who literally had someone filming him and every time he got rejected he would just look at the camera. that's all he did, he would just stare at the camera. but his camera was real, mine is imaginary.

Hilarious! Hahaha

lol! does it go like this? http://replygif.net/1408.

You should really stop that.

Op, just walk with them. If they're walking and your at a stand still they won't stop to chat. You need to walk up by them and continue to walk with them. If they shoot of into a store it's a whole other situation entirely.

It was an expressionless look. no smiling, no frowning, nothing.
I just googled "man looking at camera" this is the closest example I could find.

Does the Curb Your Enthusiasm theme song play in your head whilst making this deadpan face?