When in dream state, the brain is not resting – it’s actually very active. Lucid dreaming happens when brain chemistry is in a similar state to being awake, somewhere between asleep and awake.
So the REM state (the dreaming stage about an hour before you normally wake up) is the lucid dreaming hotspot.
The best way to go lucid is to break up your sleep. If you can wake yourself up for 20 minutes to an hour in the early morning and then go back to sleep, the chances of having a lucid dream increase dramatically.
But dreamers beware: the more we try to control things, the more likely the dream is to slip away.