First of all, take all the advice given above, I think it is very helpful and I won't repeat it because that would be unnecessary.
I would like to add:
Whenever I'm feeling unmotivated to do my work, I always think about my goals. Do you want to live in NYC, Paris, Milan..do you want to have a job you love, live in an incredible apartment, have children. I usually go on Pinterest and make a sort of 'dream life moodboard' and use it to motivate myself into working, which I see as the key to my dream life!