In one sentence, describe what the following article is about:

A lot of people act in ways that show disinterest and dislike without even realizing it. Figure out if there's anything that you do—or don't do—that may make you seem closed off, and try doing the opposite to look more open.  Are you shy and quiet? Unfortunately, shyness is often misinterpreted by others as arrogance. Try to turn this assumption around by talking to people more often. What's your body language like? Many people look closed off without meaning to be. When you cross your arms, fidget, slouch, avoid eye contact, or rarely smile, you look less approachable to other people. Sometimes people aren't open due to negative past experiences, chemical imbalances, or neurological disorders. While self-help may work for some issues, others require the help of professionals to resolve.  Depending on your problem, you may talk to a counselor, a therapist, your primary care physician, a psychiatrist, or some combination thereof. If you're having trouble opening up due to a fear of social situations, you may have social anxiety. Certain mental illnesses, neurodevelopmental disorders, and neuromuscular diseases can affect your ability to communicate nonverbally, making looking more open difficult.  Some people may have trouble opening up because of past trauma or a lack of ability to trust others. A professional counselor can help you work through these issues and regain your ability to trust, allowing you to be more open. You don't have to change the positive or neutral aspects of your personality just to be more open. If you're comfortable with yourself and have fulfilling interpersonal relationships, then you might already be an open person in your own way. There's nothing wrong with being who you are.  If you're introverted, don't try to be extroverted. Since many cultures are biased towards extroverts, it may be tempting to force yourself into a more extroverted persona. However, this can lead to burnout and unhappiness over time. Instead, find the right balance of social interaction that makes you happy and stick with it.  If you're autistic, you're likely to have some trouble with typical nonverbal expression. You may want to learn how to do things like maintain appropriate eye contact and smile more often to help with social situations at school and work. Keep in mind that most people have to "perform" the same way on some level, even if it may come to them a little more naturally. Also, if you struggle with these things, don't beat yourself up over it. Just try your best.

Summary:
Think about why you may be considered closed off. Consider talking to a professional. Remember that there are many types of open people.