Wake Back to Bed or WBTB Lucid Dreaming, is where you wake up after 6 hours of sleep, then stay up for anywhere from just a bathroom trip to staying up for 60 minutes and then go back to bed.
If up longer than a bathroom trip, turn on the lights and do lucid dreaming related reading. Only stay up until you can think clearly, and are still tired enough to go back without any problems.
Wake Back to Bed Lucid Dreaming is used mainly with the WILD technique. But you can use it also to get Dream Induced Lucid Dreams. The idea is that you wake up your mind, when normally it would be sleeping, so when you go back to sleep it's easier for you to become aware in your dreams.