To help you activate, be persistent and keep up the intensity of your goal a positive attitude is very beneficial. Positive thinking will help you believe in yourself and therefore help motivate you. Achieving your goals is something only you can make yourself do and although motivation is best when it comes from within it is also helpful to meet up with a group of people and talk to them about what you want to achieve. This helps you with your motivation because you are actively setting aside the time to go through what it is you want to achieve and discussing this with others can help you realise how to reach your aims. This then helps you turn your positive thinking into positive action.
Positive thinking on its own is not always beneficial. It can give you a positive outlook but to achieve goals you must take action. Have a look at the following article on the “as if” principle and the list of exercises you can practice based on the principle to achieve: happiness, will power, persistence, confidence...and much more.