All as above mate. But make sure you carry your documents too, if you do get pulled over best to have them so you can get on your way quicker. Carry cash just in case too
Have you been on the Nurburgring before? If not bear in mind you mostly likely won't be insured. And that its not a race track anymore. Drive it like it is, without respect, and it will bite you hard! The last thing you want to do there is have an accident. Not only will you probably destroy your way home, you may have to pay for damaged armco, cover costs if they need to shut the road etc. Very very expensive! Just enjoy the car/road don't try to race and remember to check your mirrors all the time! Others may only pass you on the left so stay to the right whilst being overtaken and you'll be fine
If you haven't had the car serviced recently, would be a good idea to before you go. The 'Ring punishes your car on tyres and brakes etc