Weight loss is a bi product of knowing where you want to go and letting go of any past trauma and mistakes that you are holding on to. Focusing on diet and exercise first before the mental and emotional cause of weight gain will only result in failure once the goal is met. 97% of people that lose weight end up gaining it back when the focus is on the diet or exercise and not in creating behaviors to match what you envision your future life to look like.
Sometimes the changes we need to make are a mystery to ourselves, thats where hiring a coach comes in or finding someone you trust to hold you accountable. Consider your past experiences in trying to lose weight and then determine what you think will be the most likely path to success in your transformation journey.