Get into conversations with people who have learned, whether through school or work, a great deal about life. Speak to them, and try to understand how they obtained that knowledge. Ask them questions about subjects that you don't understand. Talk to people from a variety of professions. Education takes its form in a variety of ways. An educated man realizes this. Your mechanic can as knowledgeable as your professor. Find out if a scholar or writer is giving a talk in your neighborhood. Go to the talk and listen to what they have to say. Often, after a talk, a question and answer session is held. Not only will you learn about a subject, but you will also be able to ask the lecturer questions directly. Again, try to take accurate notes. This will make it easier for you to come up with good, stimulating questions that will allow for an invigorating discussion. Of course, don't tire yourself writing down every word. Remember, you just want to mark down key concepts and ideas. During the course of your conversations, you will almost certainly end up disagreeing with the person you are conversing with. Try to understand their viewpoint. This does not mean that you need to agree with everything you hear. This would be foolish. However, an educated man does not dismiss someone based on a disagreement. Actually, arguments and debates show that you are willing to entertain ideas that are different from your own. They help you to develop your own point of view. If you disagree with a perspective, you could say: "I see why you would think this. However, I have a different take on the matter."

Summary:
Talk to people who are reasonably educated. Go to public lectures. Stay open-minded.