Your actions define who you are. To change your identity, first, decide what new identity you want to have, and then what actions that type of person does. Doing these actions will give you proof of your new identity.
Decide the type of person you want to be.
What do you want to stand for? What are your principles and values? Who do you wish to become? To figure out the answer, ask questions like, “Who is the type of person that could learn a new language?” The answer to such a question will define the identity you must have.
Prove it to yourself with small wins.
Once you decide what identity you want to have, ask yourself what actions that type of person does. If you want to lose weight, ask, “What would a thinner person do?”