Be the best you can be

There are a lot of people who think they will make it big in life but end up being a hobo. You hear everyone talking about how they are gonna be the star of a football game or the star actor, in reality there is a slim chance that will happen. We all know that everyone cant be the star of the show. Not to get anyone's hopes down, be the best you can be and follow your dreams but you have to know a realistic goal from a fantasy. I am a person who wants to make the best of myself and attend college to have a good and steady career. The only thing that can stand in my way at this point is myself. My friend on the other hand plans to party all through college and plans to marry rich so they wont have to lift a finger. Its truly a lazy factor that comes into play but what if that plan fails. What will she do? I don't think she thought it out all the way so i explain to her that not everything goes perfectly as planned. So my question to you is how does someone keep their self from being the best they can be? I know the obvious answers, I'm looking for deep and meaningful thoughts.