A simple formula for succeeding in your goals is to make SMART goals.
S = specific
M = measurable
A = attainable
R = realistic
T = timely
A goal such as "I hope to reach my desired weight by the end of the year." is not a SMART goal.
How much weight exactly do you want to lose? When will you start? In what timeframe? How much do you weigh now? Will you get any help? Join a club? Join a gym? What clothing size are you aiming for? Change your dieting habits? Break this goal down by weekly, monthly, and/or quarterly achievements.
Apply the who, what, when, where, why.
By being SMART in setting any goal, you have a better chance of achieving your plans.