So if I use the affirmation/mantra, "I will realise I am dreaming" how can we be sure the subconscious mind knows what we are talking about? How do we know when we are making affirmations about things as unquantifiable as lucidity that the subconscious isn't getting its wires crossed and actualising our desire in the waking world instead of the dream world?

And what does it mean to "Realise" you are dreaming? How can I realise I'm dreaming when in a lot of my waking hours I don't even realise I'm awake - thanks to habitual behaviour?