This is a scene from "High School USA." In this cartoon, we see the character's tongue touching the area just behind her upper front teeth to pronounce the L correctly. If even cartoon characters do it, why shouldn't you?
Notice the difference in pronunciation between "Phil" and "feel" in this scene from the pilot of "Modern Family."
Practicing pronunciation is very important. If you really want to improve, repeat, repeat and repeat. Imitating native speakers is a very good way to do it. Watch this scene from "Devious Maids".
* She's Puerto Rican. She wants to be a singer and her producer tells her she has to lose the accent.
************* Credit to the words and video - http://www.youtube.com/user/learnwithvideos