Finding motivation is easier than it looks! It all comes down to starting it! Once you start taking the steps toward fitness, you start to notice the differences in how you feel and how you look and you start to feel a sense of accomplishment. Each success brings you more motivation.
For me, because I have such a large amount to lose, I set myself a bunch of mini goals that are more easily achieved. It feels great to reach one of those goals and in turn, it helps inspire me to keep at this, because not only am I seeing my success, but it's not too far to get to the next mini goal.
I think that was where I failed the first time I tried to lose weight (many years ago) - I kept my eyes on the long-term goal and had no in-between goals to keep me feeling good about my success in the meantime. Eventually, it all just seemed so overwhelming that I stopped, after losing 50 pounds, trying.
If you don't have a lot of weight to lose, mini goals don't have to be weight loss ones. You can set goals for things like having more energy, how your clothes fit, going a week without having anything processed and bad for you, seeing your legs get more toned, gaining more confidence, feeling healthier, improving things like blood pressure, fitness levels, etc. There are lots of rewards to weight loss that are in addition to the actual weight loss itself. And each small difference your new healthy lifestyle achieves for you is another mini goal reached and another success for you to celebrate along the way!