Set a goal and achieve it.
You can only get what you want, if you know what your goal is. Otherwise, you will be meandering aimlessly with a vague sense that something is wrong, however, you will not be able to pinpoint what exactly that is.
Clearly define what you want - and expect the best out of it.
If you don’t know what you want, you will not be able to achieve it. For example, you may want to get a promotion at work soon. Your expectation should be as high as possible - tell yourself that you will get the promotion by the end of the year for example. Leave no room for self-doubt.
Be sure that this is the right objective.
Ask yourself, “Is this really what I want? Is this really what is best for me?” If the answer is yes, then you can follow through with achieving that goal.
Change yourself in a manner that will allow your goal to come to you.
For example, if you want to get that promotion, identify why you haven't yet. Maybe you have poor time management skills or maybe you do not have enough patience. Then, change those things about yourself.
When you begin to doubt your ability to achieve your goal, tell yourself "I can do it."
Simply saying those words out loud can have a tremendous impact on your motivation.