1. You don't need to be a runner to lose weight
Everyone associates running and doing strenuous cardio with weight loss and at first I thought that the only way to lose weight was to become a runner. I can first and foremost tell you that this is not true. There are many studies that have shown that doing weight training and building lean muscle mass will help you burn more calories over a longer period of time and thus help you to burn fat quicker. That is the important part - burn fat - as it is fat and not muscle that you want to be burning. Running and cardio exercise is great for increasing your fitness and it does help you to burn fat, but it is very important that runners still do a weight training program so that they do not lose any of their lean muscle mass.
2. Learn to be disciplined
Everyone says that motivation is the key to success. And I agree it is, but motivation will only get you so far. There will be those days at 5am when it's pitch black and you don't feel like working out or those days when you've been at the office for 10 hours and now have to think about going to the gym - no amount of motivation will get you going for that run or to the gym. That is when discipline kicks in. It is discipline that will get you out of bed when that alarm first goes off. It is discipline that will keep you working out 5 days a week and it is discipline and that routine that you get into making lunches for work everyday that is going to stop you from buying your lunch out.
3. Find your "why" an do what you love.
I always tell my clients to find their "why". Why they are doing something is going to have such a bearing on their end results. If you are doing something for the wrong reasons or are motivated by outside factors then it is going to be hard to stick to it and to stay motivated. For example If you are only doing a type of exercising or eating a certain type of way because someone tells you that you have too (e.g someone says you need to start running to lose weight but actually hate running). Then that motivation is not going to last very long - after a week of forcing yourself to go for a run you are more than likely going to throw in the towel and give up. Exercising and eating well do not have to be hard and should be about you doing something that you love. There are many ways to exercise and get healthy - running, cycling, swimming, dancing, weight lifting, playing sports (e.g. tennis, rugby) so the key is to find something that you love and that you'll be able to stick too.
4. Taking rest days is just as important as working out
Taking the time to let your muscle rest and repair is just as important as the workout session that made them that sore to begin with. It is when you are resting that your muscles rebuild and you get stronger and fitter. Not listening to your body and resting when it is tired will not only lead to overtraining but can also lead to burnout and a forced rest if you get a serious injury. In saying that, don't say "I need a rest day" 6 days in a row. Usually 2 or 3 rest days per week is sufficient and I even encourage my clients to have active rest days where you go for a walk or a swim or something that is active but not too strenuous.
5. Look for reasons besides aesthetics to get you motivated.
For me this is a big one. I am a firm believer in having other goals and motivation besides losing weight and aesthetic goals. Yes that can be a great motivator for people when they see themselves losing weight but this can also lead to people being obsession with weighing their foods and taking progress photos and can lead to very unhealthy habits. Have a fitness goal (run 5km or 10km) an event that you want to compete in or set yourself some other goals e.g. cooking 5 nights per week with only 2 meals out on the weekends.