Achievement never happens for its own sake. Achievement is built when there are solid, meaningful reasons behind it.
The only enduring impediment to success is the lack of a reason for that success. Connect with a good reason, keep that connection strong, and you will find your way through whatever challenges you encounter.
When you have a reason, you have a stake in the outcome. When you have a reason, you're able to summon the discipline, commitment, persistence and creativity necessary to get the job done.
The best motivation is not to be found in some sophisticated secret techniques or procedures. The best motivation is to constantly keep yourself in contact with your reason.
Give yourself plenty of reasons to succeed. And you most assuredly will.