I've seen some hypnosis audio files online before that are supposed to help you train yourself to wake up in a wet bed without knowing.
You could also just start wetting the bed when you feel the urge to get up and go to the bathroom. When you feel the urge to pee when you're asleep and in bed then just try to urinate while lying in bed and you might eventually be able to wake up wet without knowing in 6 months to a year.