If your school offers it, take a review course. If not, buy a NCLEX review book and make it your best friend until you take your boards.
Above all, the night before your boards, stop all reviews or studying around 5pm, have a nice dinner, have a quiet, relaxing night without thinking about nursing (but no drinkie!), and go to bed early. I fould it helped to not stay up til the wee hours over my review book cramming details in.
No matter what, you'll be nervous as heck taking your boards. So take it very easy the night before. You made it this far, you can pass the boards!