You would want to try adjusting your wbtb time and/or how long you stay up for wbtb. So maybe adjust to 5:30 hrs of sleep, or if you wake up after 6 hrs, maybe stay in bed and recite an affirmation instead of getting out of bed and waking up too much. If your sleep schedule is regular, it will be just a matter of fine tuning your wbtb schedule to see at what point are your able to wake up, but then be able to fall back asleep too. That's all I know about wbtb.
Just slept 5.5 hours, and stayed awake for five minutes. I was unable to fall back asleep, again. I've concluded that I should do affirmations instead. Do affirmations mean repeating "I will lucid dream"?