Death reflection: When are you going to die? You can only be lazy so long if you reflect on death coming at any moment: Do you want to die lazy? Is that the image you want? Reflecting on death gives us more energy, it stimulates us to think about what to do in life rather than to just lay back and do nothing.
You have to stimulate yourself. There is a Pali word, Samvega which means developing an urgency, a wish, a desire to get on to do something. It's a motivating factor, we want to work harder. Now with the Dhamma practice it can be hard, it can be frustrating, it can be boring, but what are you doing it for? You have to continually remind yourself what you are doing the Dhamma practice for, you have to stimulate your own interest. Interest is a key word, interest is totally opposite to laziness. Anytime you are interested in something, you are not lazy, you want to do it.
Here's a clear example of how interest can override even physical exhaustion. If it has never happened to you I'm sure that most, if not all of you can identify with it: You've been working on a project at work for 3 weeks, everybody has been working flat out, there has been a lot of overtime, people have been working on the weekends. It has been exhausting. Finally on Friday night the job is done, everyone is really happy, everyone is totally exhausted, the job is finally done. All you want to do is go home, maybe have a drink of juice and hit the bed, you don't even what to change your clothes. You just want to sleep for 12 hours straight. You get home, a note tacked onto the door. You take it off and read it, and realize it's from a friend you haven't seen in three years. "Hey, I'm in town just for the night, can we get together?" Are you going to go to bed when you haven't seen a good friend in three years? Most people are not, they're going to all of a sudden have lots of interest, all of a sudden they are going to have lots of energy to spend with their friend that they haven't seen in three years.
So interest is a key element to combat laziness. So ignite your interest as to what you are doing here. Remind yourself of the importance of the practice, remind yourself that death may come at any time. These are ways to stimulate more energy to let go of laziness.