I think that philosophy is very difficult for someone who know nothing about it and want to learn. In order to learn philosophy we must start at the beginning. Ordinarily, I would suggest that we learn by studying the great philosophers of history. But such a thing is no good to someone who lacks any philosophical knowledge at all. Philosophy begins by explaining what it is, why it is studied and starts with what is self-evident.
Philosophy is the study of foundational truths about reality. At this point, I am simply stipulating this definition, although philosophers will agree with my once I explain what I mean. A foundational truth is a truth that is at the most basic and general level. For example, if science is best or only way of discovering reality, then philosophy is a discussion of the fundamental truths of science. If mysticism is the way of discovering reality, then philosophy is about the fundamental truths of mysticism. Or, if philosophy is a way of discovering reality, then philosophy is about the nature of that fundamental reality.
Philosophy is important for our knowledge. In order to understand the way the world really is, our place in that world, the way we should act and believe in that world and how our knowledge exists and relates we need philosophy. Philosophy has no direct practical value. Without philosophy, we could still do everyday tasks. Logical skills, speaking skills and knowledge of the past do have practical value, but they do not form the core of philosophy. Having said that, philosophy has the greatest practical value indirectly. The difference between living a useless life and an examined life is found in philosophy. Philosophy gives us our place in the world, shows us what is valuable and explains the basics of the world to us. Without it, we are like mere animals.
Philosophy starts with what is self evident. Something self evident is obvious. We must begin with what is obvious to us and reason to what is most fundamental. We reason to what is most fundamental because that is the point of studying philosophy. But we must start with what is obvious to us for a number of reasons. First, we must avoid circular reasoning. Circular reasoning happens when the conclusion of the argument is more obvious than the premises. For example, “God exists because the Bible says so” is a bad argument because the existence of God is much more evident than the truth of the Bible. The fundamental truths of reality are much less evident than what is obvious to us. So we must begin with what is more obvious than those truths. Second, we must begin with what is self-evident because our argument will not be circular no matter what it attempts to prove. Since the premises are the most obvious, the conclusion must be less obvious. Finally, such an beginning is practically valuable because the obvious truths of the world are known to all people.