I want to do really good in school this year?

I'm entering sopre year. I ped freshman year with A's, B's, C's, and D's, mostly B's. I want to do SO much better this year. I'm a huge procrastinator, lazy too. I do get all my work done, but I just don't set a high grade on them. I'm not a good tester. I have a hard time remembering things. What can I do to motivate myself and help do better in school?