You are asking one of the most important questions any human could ever ask Positive attitude combined with the belief in exciting goals has worked for many people, and it's working pretty good for me on most days:
“Belief gives you the power to achieve the extraordinary.” Chris Powell
“If I have the belief that I can do it, I shall surely acquire the capacity to do it even if I may not have it at the beginning.” Gandhi
“Belief has the power to change your inner state and your outer world.” John Paul Warren