How to change people

Self-concept has many definitions but they all have the same meaning, which is, your perception of yourself and of your abilities. When I ask you to describe yourself in one page, you will dump all you think about yourself. The way you view your capabilities is called "Self-concept".
Examples of Self concept could be:
“I am a sociable person”
“I can solve any problem”
“I am fat”
“I am unattractive”
“I am clumsy”
“I am uncontrollable”
The most dangerous thing about having a distorted self-concept is that your subconscious mind always works to fulfill yourself concept. For example, if you see yourself as an unattractive person then you won’t try to be attractive. This self-concept may hinder you from trying to follow a healthy diet, make you buy unattractive clothes and even force you to act in an unattractive way!!
Trying to become attractive without changing your self-concept will never work. You will feel that there is something artificial in your behavior. If you want to change something about yourself then you have to understand that you must begin by changing your self-concept.
If your self-concept is that you are clumsy, you will always act accordingly to that even if you try your best to conceal that side of you. The self-concept is stored in the subconscious mind. The harder you try to do something that doesn’t match with your self-concept, the more you will find your attempts useless.
A salesperson who has a self-concept of being a failure will always fail to meet his target. A guy who has a self-concept of lacking confidence will always act without confidence even if he tries hard. The athlete with a self-concept of not having the ability to win the gold medal will never get it.
To summarize this, it's almost impossible to challenge your self-concept and that’s why you should try to change it instead of challenging it.
Suppose that someone has a self-concept of being persistent, how do you think this will impact his behavior? This person will keep trying to reach his goals even if he failed hundreds of times. On the other hand, if his self-concept was that he was a victim, he would have given up after the first try!!!
So it's all about the self-concept. Having a self-concept of being motivated will result in making you motivated, and having a self-concept of being successful will result in making you successful.
When you upgrade your self-concept, your subconscious mind will change everything accordingly in order to fulfill that self-concept, so just change your self-concept and let your subconscious mind do the adjustments.
You are what you think. So if you want to change something about yourself start by changing your self-concept first and then you will find the change happening effortlessly.
So what does all this have to do with relationships? One of the biggest mistake people make in a relationship is trying to change someone by convincing them that they’re bad. For example, telling your husband that he is irresponsible and that he is in a deep need to become responsible will only result in changing his self concept to being an irresponsible person.
A man who keeps telling his son “you’re stupid! You need to study more” will help his son to develop a self concept of being less intelligent than other people. The correct way to change a person is not by tell them that they’re bad and need to become good but rather by telling them that they are better than their current behavior.
If this man told his son that he is a very smart and that these grades do not belong to someone with mental abilities like his, then the son will try to match the self concept his father formed.
If you want to convince your partner to stop smoking then the first thing you should do is to convince him/her that he/she is not a smoker but is rather someone who smokes. Tell your partner that he/she doesn’t belong to this category of unhealthy people and that they are much better than the behavior they are doing and you will notice the change that will happen to them.
If you want to change someone, upgrade his/her self concept first then help them stick to their new self concept.