Personally i think, as a sub, i give off subtle signals with out intending too. Simple things some days... like how i might respond to a question with a "yes Sir or No Ma'am" response and the tone of voice and expression behind it. How my expression may change when something is said that is a trigger of some sort... even how i may sit or hold my hands/arms.

But, i also think that they are signals that only another person in the same lifestyle would pick up on and in some cases only someone in the same lifestyle who knows me fairly well (although doesn't know of my interest) could pick up on. For the most part i think the signs are subtle enough that most "vanilla" people would not pick up on the true meaning behind them. Although any red blooded male might pick up on the sexual innuendo they perhaps might hide.