One of the first steps for preparing to have lucid dreams is to start keeping a dream journal. Any time that you remember a dream, write it down in your journal. Even if it's just a fragment of a dream or a lingering feeling, write it down. The journal will help you notice what your dreams are like. You will probably find that certain things reoccur in your dreams on a regular basis. These things are called "dreamsigns" and with practice you can learn to recognize dreamsigns while in a dream and then become lucid.
Most people remember very few dreams. In fact, it's quite possible that you have already had a lucid dream and not remembered it! Keeping a dream journal next to your bed will improve your ability to remember dreams. Get into the habit of lying in bed for a few minutes after you wake up and try to remember any dreams that you might have had.
Once you are able to recall at least one dream per night, you will have a good chance at having a lucid dream.
Deck Memorization Have your friend shuffle the deck. Now, go through the cards and use the link system to link each card to its neighbor. For example, if the ten of diamonds (keyword=dice) is adjacent to the two of hearts (keyword=hen), you could form a visual association of a hen laying some dice instead of eggs. With practice you should be able to go through the entire deck in a few minutes. Now you can recite the entire deck from memory by going through your link list and remembering the keywords.
This is considered by some to be the ultimate tool. With its waterproof properties, it was quickly adopted for a specific military application when originally introduced. The US Government also has recommended that all homes have it available. Along with its waterproof properties, it is known for its superior bonding, is heat resistant, and is extremely strong. It is easy to use with no training required, and is widely available in various sizes and colors. NASA thinks so highly of this, it is included on every flight that leaves the launch pad. No home, military unit, or spacecraft should be without it.