For anyone not familiar, a common class of techniques people used to use (still do? Not mentioned in the article) involve regularly testing yourself to see if you're in a dream. Counting your fingers; in dreams, you may not have 5 per finger. (Sound familiar from a modern take?) Or, look at numbers and words; a digital clock; in dreams they may not make sense, but in real life they do. (OK, this is really sounding familiar...)

The idea is that when you check while awake, you will pass the awake-check, but set up a habit pattern. While dreaming, you will observe weird stuff when this happens, realize it must then you must be dreaming; you then become lucid, and can sort of control the dream, or at least be aware you're dreaming.

It may or may not have worked for me a handful of times. It certainly felt so, but only briefly, and I can't confirm it was the desired effect. Would wake up shortly after each time.