Getting yourself to your choice of CCNA testing centers is the second step after visiting prometric.com or vue.com and registering for the exam. This information isn't exclusive only to the ccna exam but to all. The procedure is the same...
You will be asked to show 2 forms of valid ID, one of which ccna test has to be a photo id. When you register for your exam you will read exactly what is accepted. Passport and driving licence is always accepted
You will be asked to sign the log book when you arrive and when you leave
You have to sign the agreement that you will follow the rules
You may be given a sheet of scrap paper and pen/pencil if it's needed for your exam.
They will ask you to leave any personal items Spoto with them. You can't for instance take your bag, phone etc into the exam room.
You will be shown into the exam room where your test would have been preloaded ready for you to start.
Some ccna testing centers will inform you that the exam room may be audio or video taped. Most of the ones I attended didn't, but 2 of them did. So don't naively try to talk to someone else taking the exam.