It may also help to use "awareness" as a tool here.
When your legs become restless, or you feel the urge to yawn, or have this really annoying itch on your nose, or feel a cough coming up, usually these are indeed signs that you are not completely calm, or you might be entering the calm if it happens halfway through the meditation.
I myself have even noticed that I am about to reach the deepest part of my meditation as soon as my face starts to itch around the eyes and nose.
When this feeling comes up, focus on it fully through awareness.
This is a bit tricky, as usually when we focus, your mind will want to start working and make you think about the itch or restlessness or even pain in your left buttock ( to name a few ).
This is something you have to be carefull of, as thoughts will enhance the feeling you are experiencing.
If you try to stay cool and look at it indifferently, without thinking about it, but fully undergoing the experience of itch or pain by observing it without thought or judgement, it will usually magically disappear.
Even with itches, my personal torture, I not only notice the itch completely disappearing, it also takes away my neurotic compulsion to scratch anyway, even when the itch is gone, something I still can't seem to accomplish outside of meditation
I hope that helps
