Dogs are great role models. They are always living in and for the moment. They give their full attention to whomever or whatever they are engaged with. They give their all to a game of fetch, licking your face or just cuddling. They aren't disappointed by expectations. They don't hold grudges. They love life.
Always make a quality effort. Whatever task you are faced with is to focus of your life at that moment. Why not choose to complete it to the best of your ability? Even a menial or unsavory task can bring you satisfaction for a job well done. Why waste this precious life moment feeling annoyed at having to do this work and at your mediocre effort to get beyond it? You can feel satisfied and fulfilled in any moment if you give it your all.
Why do people spend so much time strengthening their strengths? My observations in the gym are of people doing the same exercises with which they are comfortable and have at least a base level of, if not substantial, strength. (Guys with a big upper body and no butt or legs; people who do the same ab work and cardio machines.) The most fertile ground for personal growth (whether emotional, intellectual or physical) is your weaknesses. Consider what you'd like to improve about yourself and make a plan to start doing so. Otherwise, you'll suffer from an imbalance that you may not realize is an obstacle to getting the most out of life.
"Nothing is a waste of time if you use the experience wisely" - Rodin. What if you approached every task and interaction, enjoyable or not, as a potential learning experience. To open your mind. To better understand yourself, others or the world around you. To improve your skills. To test the strength of your convictions. To see beauty or wonder in your surroundings. Try it. You'll never waste time again.
Why worry in advance? Think of the time that we can waste worrying about an event or outcome that you can't control. You could use that time and energy making progress toward one of your goals. Plant the seeds for your future growth and progress. Keep working hard to better what you can control. Stay busy improving your life and deal with events as they come.
Progress, not perfection. There is plenty that we can do every day to better our lives and the world. It doesn't need to be part of a grand plan, particularly if you don't act because you are waiting for the perfect moment to do so. Make some notes of the things you'd like to improve, people you'd like to be more connected with, good you'd like to do for others. Do something today that helps you and the world, no matter how small it may be.