2 big reasons for losing a lucid dream are a sudden lack of focus, and a conflict in what's going on in the LD and what physical reality allows a person to do (ie; floating can't be done in the physical so the mind rejects it)
When I first started LD'ing, the first few times anyway, I'd excite myself right out of it. I'd think "wow, I'm dreaming and I have control, whoot whoot!" and then I'd be awake and miffed. What happened there wasn't so much the excitement as it was a LOSS OF FOCUS. You cannot remain lucid without focus in the dream.
The initial excitement will pass as you LD a few times, but the focus issue remains. When you become used to focusing the second issue regarding the conflict of the waking mind and the possibilities in the dreamworld sort of level out, allowing even more focus.
Here's a trick I've come to learn and utilize when lucid dreaming to improve focus; when lucid and calm, start turning around slowly like a spinning top. Maintain your focus throughout this exercise. If you start to lose focus stop spinning and get your composure, then start again. This will accomplish several things....
- You begin to realize that you are not facing 'one' direction when you dream, you can take in all that is 'around' you and oddly enough, this makes it EASIER to focus because you aren't getting buried in the details of ONE thing. Focus becomes easier and the spinning sensation will cease, but you will be -more- aware.
- Your surroundings disappear, allowing you to construct your own dream, or allow another to seep in. You'll also eventually come to realize that this LD realm is a wonderful place from which to launch other experiences. Knowing then that you are inside your own mind, you now have the ability to exit, not as an astral body, rather then as a point of awareness only. (this leads to a completely different subject tho)
- The conflicts between the mindset of the physical and the dreamworld will eventually disappear as you become used to manipulating yourself in the dream world. The spinning enhances and speeds up this realization, why, I'm not sure.
Worked for me anyway [

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