Here's an interesting idea for you all to try. I know that this will sound obvious but it is fun just the same. Watch the TV with the volume turned off. I realise that actors will use body language more than most of us do in r/l-but the signals stay the same. I can guarantee that you will still be able to follow most of what is going on by reading those signs. After all, most human communication is done through body language-an old hang-up of mine when discussing the limitations of on-line communication.
A few of you will know that I really find typing like this, especially when chatting to be too restrictive. I prefer voice for certain subjects as I have failed miserably in the past to convey my meaning with any accuracy.
For those of you that get the chance-watch the British comedy film "Kinky Boots" It isn't that kinky I hastily say, but very funny. The point is though that there is one scene when the heroine has a dance with an extremely camp character. He is carrying a riding crop. He may not be her idea of the perfect partner-but watch her body language. It left me in no doubt about her desires and is possibly one of the most erotic scenes I have ever watched. She says nothing and does very little-but...but...watch it and find out if you agree with me.
Oh! And cariad-why limit your question just to subs? Have you never experienced Dom/mes giving off signals. (Say like at a dance? *weg*)