If a person has an inner self confidence, they will carry themselves in a way that when they walk into a room, people will notice them.
There is confidence in yourself, your abilities and in what you can do.
If you believe that you can do it, others will too, will want to be around you and benefit from your success.
This needs to be from the positivity of doing things well, not about the arrogance of being better than others and looking down on others. This positive confidence then also spreads onto others and benefits them, you believe that they can do it too.
It means you believe you can do it, know you can do it and not have any fear.
A person builds up confidence from the reality of their achievements, otherwise it is just a delusion which is a road to eventual ruin. You need to know the truth of when something is not working, so that you can resolve it.
To come over as confident you need to 100% do things, not do them in part or in halves. People without confidence are uncertain and do not do things wholy, properly and in full because they are not sure about them. This affects everything you do. For example some people even look insecure when standing as they do not think they can do that well, so do not do their posture 100% properly and just half do it.
People who are uncertain, look pathetic, especially if they are scarred, nervous and so on are a nuisance to do things with, as they are more of a liability than an asset.
In social situations it is about being confident in things you can help others with, if you do not believe you can do anything to help others, other people will think you cannot do anything to help them and they will not want to know you.
In fighting situations, if the other side thinks you are not confident, they will think you are a walk over and attack you. Also if the other side see fear, they will do movements to make you scared,blink, cower and make you run away..