When there's will, there's a way. Impossible is another word for I'm possible for someone whose will is strong. Real change doesn't just happen, because change is difficult. A drug addict whose system has been diffused with it can not stop in a day, it will take first, a will, then a deliberate and constant effort until his will becomes victorious, the same goes with every change. The only reason why change seems difficult and impossible is one's unwillingness to give up things of comfort for things of greater need.
Natural change is constant, but attitudinal change requires a will. It's first to desire a change, build stronger will and put much effort into it.
The first step to change is learning to say no, no to things you wish to let go, no to things which had held you back, and no to remaining the man you've hated for years. It takes a strong will to say No, and when one has mastered this act, then the process of change begins.
Ever struggled to change? There's likely two reasons for it. It's either one has not mastered the act of saying No, or one is yet to build a strong will to change. All that's required for the world to change is will, the will to want to be different, the will to want to make a change, the will to desire a better us.
All you need to change is will, and it starts from the inside, a strong hate for who you've been or what you want to change, and put on a will ready to sacrifice whatever is it to be who you wish to become.