I can’t reccomend books outside of the basics of meditation. Most of it requires some work to be put in with body mindfulness.

Next time you are about to fall asleep, try to program your brain to find out something that’s meaningful to you. Just keep telling yourself that you are going to find that thing. And when you do, you will KNOW it’s a dream. Keep telling yourself to test reality in your dreams.

Its ALL about breaking the waking and the non waking barriers

It will take time to master those powers and the night that you do you will wake up like you just took LSD. Even still, keep that dream object and reality testing in mind. The more you do the more you will find yourself testing if it’s a dream in the dream. That will set it off.

You can even test if you are in a dream IRL a few time a day to speed things up. It sounds silly to do, but it will train your mind to test reality in dreams.