The first is pronounced with the tip of the tongue at the alveolar ridge. The second is in the back of the throat with the root of the tongue, close to the uvula area of the mouth. This second 'l' is called the "dark /l" and is the focus of this lesson. You'll probably notice that it sometimes sounds like the /o/ vowel sound. Be sure to contract the back of your throat, however, as you say it this way