Each of my cats has a particular way to let me know when she/he wants to go outside. A couple stand by the door and wait for me to notice. One jumps at the door knob. These are things that I am sure of.
Callie is a bit tougher to understand. She jumps on a shelf by my laptop computer and puts her foot on the mini-blinds of the window. I am not always sure if she wants to GO out, or just LOOK out.
I wonder where I can take a course on learning to speak "Meow".