Don’t set goals that are impossible to achieve. For instance, “I’m going to lose 15 lbs by February.” This is not a practical goal. Not because of the weight and time frame, but because of the fact that you are trying to lose something that you many have no idea how to track. How do you know if you are losing fat vs. gaining muscle vs. what is water weight?
What is a more practical goal: “I am going to workout three days a week for 1 hour and bring my heart rate up to my Target Heart Rate.” Now this is something that you can track.
Unless you are a trainer, have a trainer or nutritionist, know how to measure your BMI, there is no way for you to scientifically and accurately tell if you are losing Body Fat.
Be practical when writing your goals (practical and optimistic are NOT the same thing).