There are a lot of motivational videos on the youtube. Start with them i think there is some from Silvester Stalone and Will Smith, i know that this sounds funny but it really can motivate, even you should play tham for you once a week.
Other thing i use is next to my bed write some motivational sentence it sure keeps me motivated from the begining of the day and makes my day better not only for SFI but in every aspect in my life.