Self-awareness is the key for Self-development

“Until you heal your subconscious/unconscious, it will control your life, ‘make’ you do ‘unhelpful’ things and you, being in the ‘dark’, will think that what happens is either ‘meant to be’ or that it ‘cannot be helped’. You will also think that you know ‘truth’, when instead you are ‘blinded’ by conditioning. You will always be a slave to what others once said, did to you, or caused you to experience.”
                                      Carl Gustav Jung

When you want to improve or fix a table you must first observe the subject, then you draw a conclusion of what and how it will be improved and a define a plan of action to intervene and make the changes you want on it. Self-improvement means yourself is the subject, so before you can improve and develop yourself, you must observe your daily thoughts, emotions and actions so you can see, reflect and understand yourself, opening the door for conscious change and self-improvement.
Humbleness and honesty with yourself are mandatory to be able to see clearly your flaws, most of us have ingrained what is called the self-serving bias(the propensity to credit accomplishment to our own capacities and endeavors, yet attribute failure to outside factors), meaning someone who is lazy will say to himself "im lazy today because i woke up tired", creating excuses maintaining the vicious cycle of passiveness along their life.
Self-improvement is all about identifying your habits and change them leading you to the life that you want.