A good way at achieving Lucid Dreaming is to keep a Dream journal. Keep it near your bed and write down your dream as soon as you wake up, writing it down before you forget it. Soon you'll remember your dreams much easier which will help in lucid dreaming later.
How I was able to Lucid dream is by reality checking. It's where you, during the day, check to make sure you aren't dreaming even if you're sure you are not. Flip a light switch to see if it works. Write A on your hand for awake. If you are dreaming there is a good chance your hand will look distorted or the light switch will not work correctly.
As you fall asleep you can tell yourself "I will lucid dream." or "I will realize I am asleep" and this may come up in your dream and you will realize you are in fact dreaming.
Sometimes if I am awoken by a dream I will realize it then try to go back to sleep knowing I am going back into the dream and I'll be able to control it knowing that I am in fact asleep.
Many people also have signs when they are dreaming. I do not but if when you dream you always notice something like, things being too big, people faces being blurry etc that can trigger that you are asleep.