Motivation won't be there everyday, so when it's time to workout, it's discipline that's taking over. I just get my ass up and go workout, i do my warmup and hit my program. I push myself as hard as i can in each and everyone of my workout. And after i'm done, I feel good, happy and i'm proud of myself and the motivation comes back.
Point is don't wait for motivation, it won't be there everyday, but you can bet it will come back one day or another if you push yourself into discipline.