[Jaydelart]

Question: How do you begin practicing this art?

In more detail... What excercises do you consider a starting point in introduction to Parkour?

As noted previously, it is fairly dangerous to those who are inexperienced (and even sometimes to those who are), so how would someone new get involved?
Practicing in your backyard? Or more of a case in which it is recommended that you learn from someone else?

Of course, there can be many ways to do one thing... Parkour is a good example of this.
However, I'd like to know the most common way a new person would start getting into Parkour, whether it be by self-teachings or by lessons and teachers.