DISREGARD WHAT I HAVE SAID FROM THE EARLIER REPLY.

I was saying leaving a message such as "You're dreaming, check you're not dreaming, think of something to do. YOU'RE DREAMING!" starts playing in the mind as the dream starts. Saying to myself over and over again "I will have a lucid dream" doesn't work.

Saying anything over and over again never changes anything. It's like telling information to one's self over and over again. It works if that person keep saying it over and over, but then something destracts the person and they end up forgetting what they were saying. Although if the person while hearing the information concentrates on rememering the information while recieving it, thinks about it afterwards for a few minutes, and when the person needs the information the person could focus on pulling it out of the mental archives. (I might of answered my own question.)

I could concentrate on the words and a reminder to play the message as soon I see something. The clue maybe a problem. Must of the time when people remember information is because someone had asked a question to extract the information or they have seen or heard something that reminds them of the information and it comes up. To have information come up from a chosen unrelated clue is more difficult.
But it is possible.

That scene is from 'Willy Wonka and the Chocolate Factory' from the book 'Charlie and the Chocolate Factory'. The movie 'Charlie and the Chocolate Factory' is the one with Johnny Depp. I was not offended I just thought you wanted to know.