Bad vision while lucid? Here is the trick!

Hello fellow dreamers.
Recently I finished great book from Carlos Castaneda Temple of Dreams.
He had problems with dream vision, and his dream spirit guide told him to
press the tounge against upper front teeth.

Did someone tried this technique? And is it working?

Also my second question is:
Is there any RC which doesn’t require moving your body?
And if not, can you figure out some mind trick to recognize a dream?

Thanks for your answers.

Never heard of it, but feel free to try.

Yes, there are a few RC’s involving the mind. One of the most popular ones: Think about how you got here. Usually in dreams you won’t remember how you came to a certain place, you won’t be able to track your history of actions, making you lucid.
Another one is simply asking yourself awareness-raising questions like Am I dreaming? There’s a good chance that asking this will make you lucid instantly as well.