This can be anything from "I am fit, trim, and healthy" to reciting the reasons you want to lose the weight. It keeps those goals in the front of your mind and will help to keep you going!
Whenever I find a workout is getting really hard and I don't feel I can complete it, I smile. Smiling makes the rest of your body feel happy and allows you to be able to keep going because you know you can!
Take time during your walk or whenever to repeat this phrase as many times as you want: I believe in me. This will get your subconscious mind to start thinking about things in a totally different way and you will be able to succeed! I believe in me!
Create a "Power Mix" of songs that motivate you. Hearing them can really inspire you to get moving and reach your goals.
If you have a dog, they can be a great source of motivation. Going on walks several times a day will become a habit that they expect and ask for in their actions. Seeing their pleasure will help you to go for your goals too!
Whenever there's something small I need to do, recycling or putting away something small there's a voice in my head that says "I can do it later." Instead of listening to that voice, I say "No, I can do it now." Slowly it'll help with the big things too like working out and eating reasonably portion...