I wasn't sure what you meant but I guess you were asking how to lucid dream.
1. Start keeping a dream journal to help you with dream recall. The trick to this is that it forces you to wake all the way up as soon as you're awake and write down your dreams when you still remember them, this way you don't forget them over the course of the day like people tend to do, then go back and read it if you forgot what you dreamt that day. Dream recall is usually the first step people take to lucidity.
2. Next is to figure out a reality check that works best for you. For a lot of people it's pinching yourself continuously. You have to get in the habit of doing it through the day in order to remember it when you start dreaming. For me it's twirling my fingers the way I twirl a pen, because I did it habitually and got used to the weight, so when I started trying to do it in a dream I realized quickly that it wasn't real, but I've never heard of this working for anyone else.
There's a new thing that a lot of people getting into lucid dreaming swear by which is some weird method of tightening and relaxing the muscles in your fingers that people do while falling asleep. But I don't know much about it other than that it's supposed to be easier and deliver quick results.
3. Next is just a matter of being consistent with it until you realize you're in a dream. After that it's just working on your dreamscape and (for me) keeping your sleep schedule consistent.