IMHO use the time you have to work on conditioning as the added 'nerves' and the pressure you are placing on yourself to do well you'll find you'll wear out quickly. You want to finish as strong as you begin. Strong spirit is the key and for kumite 'take no prisoners'. To have been accepted to take the exam is to assume you have the skills required and with that in mind you should try not to let your nerves get in the way, like previously posted meditation would be a very good thing leading up to the 'Big Day'. Wish you the best of luck and let us know how you made out.