If you are going to play a role, put your heart and soul into it.  There is a reason you speak of half-hearted efforts.  These usually result in less than optimum outcomes.  Once you put your mind on a task, match your intention with the words “I AM” and then put your heart-felt emotion into it.  Imagine the goal fully achieved.  “How wonderful is this!  I AM doing it!  I wanted this, and now I AM doing it!”  Be fully present as you do so.  You will notice a world of difference in the enjoyment and in the outcome of any task.  Common sense words once again.  Take them to heart, why don’t you?