I've written coding exams on paper several times. My advice is simple: when you study write it out. Get used to not using your computer for doing the coding so you know what it feels like.

Run through exercises for the algorithms and concepts that you expect to be quizzed on (ie. do you have to do a bubble sort? inherit a class? write a constructor? etc).

If possible ask your prof what assignments the test might be like, and if they even give you a ballpark idea of an answer, then do those assignments over and over.

I'm not the world's most amazing hacker (yet :), but I know how to write tests. I graduated with a 4.45 GPA. :P