how to procrastinate less?

I’m in college, and I need to learn some better time management; I feel like my grades are suffering and if I could space out my work a bit more instead of doing all of it right before it’s due I would be a lot less stressed out.

I tend to spend a lot of time checking email, surfing (this site included), and having my laptop around is really bad for my productivity. Even without that as a distraction I have a lot of trouble just sitting down and doing the work unless there’s the pressure of an imminent due date on me. Any ideas? Thanks!