How Long Does It Take To Learn How To Lucid Dream?
Lucid dream induction is easiest when you're dream-generation-system is highly activated AND you are simultaneously looking for a lucid dream. The looking part begins with dream-journaling and continues with application of the various LD techniques and technologies. By applying and combining time-tested tools like sleep-disruption (i.e., the Wake-Back-to-Bed method) with nootropic formulas (occasionally) and lucid goal-setting (having a plan for what to do when you are lucid), your chances of success multiply.
When you are in the right state of mind, lucid dream induction does not need to be overly complicated nor difficult. When not in the right state of mind, finding yourself inside of a dream is nearly impossible. Some drugs block the ability to lucid dream, or even recall dreams well, for over 24-hours. I'm thinking of Piracetam. Cannabis. MAOI's and SSRI's can also eliminate REM-sleep. Most substances which inhibit REM also tend to lead to a REM-rebound once the pharmacologicals wear-off.
Other factors correlated with dream recall and perceived vividness include gender (women tend to remember more dreams than men do) and stress (more stress, more dream recall). But we are each unique. Unless affected by prescribed or recreational drugs which inhibit REM-sleep, almost anyone should be able to improve their dream recall and become familiar enough with their dream-life to soon realize they are in a dream.
Also, there seems to be a sort of beginner's luck when a person first learns about lucid dreaming and/or decides they want to experience lucidity. A convenient time to practice induction techniques is on the weekends or days when you can sleep-in, and it may only take a few weeks of using these times before you will be carrying-out your dream goals.