You need the right type of motivation music and the heart to do workouts. BELIEVE!!!! :)
What motivates me is that I'm doing something to help my body stay healthy.. Plus I have a specific set of songs that I used to work out with to keep my spirits up... The best thing to do is tell yourself you can achieve anything if you just believe in yourself.
Personally i love to think of myself strutting past people who have always doubted me to some sassy music. It helps me remember why im doing this. Not for them, but for me. To prove people wrong by doing and being what they said i never could. That is more than enough motivation for myself
I always think of my goal, where I want to be at the end. When I feel tired or I can't do anther rep or minute, I tell myself not to quit; I can do it. I won't get healthy and fit without the work, and once you finish that rep or that minute of cardio you feel accomplished and good about yourself for not giving up :)