I always like have to go to the toilet 15 minutes before I have to sit the exam and I always NEED to bring 6 pens and a pencil- always needs to be the exact number of pens and pencils.
Using the loo right before an exam. Reading a book while I'm waiting for a morning exam.# Caffeine tablet and then plenty of chocolate right before I go in. If it's a maths exam, chewing gum is also quite helpful.
This worked for GCSEs for me; hopefully it will for AS exams too.
Tie my shoelaces tightly, as I'm sitting in the exam hall. There's something about having comfortable feet that makes me perform better. "fundamental strength" or something like that
I just have to get myself into a positive mindset before the exam by listening to my fav upbeat/motivating songs. If any kind of stress/ doubt creeps in I usually do horribly!
My mum gave me a ring for my GCSE's last year and i did far better than expected! (came out of biology exam crying because i did so badly, turns out I got a B)
I have a Paul t-shirt that I consider lucky for further maths (but no other subject.) It's the 'EVOLVE THIS!' one with Jesus shooting Darwin on it that the fundamentalist Christian chick wears. Since no one in my maths class seems to get the reference, I think most of them think I'm a religious extremist. Certainly they all avoid me when I'm wearing it (although that might be because it's a little worn and sweat stained - but it's clean, I swear!).
My sister does a goodluck dance for me before i leave for my exams it 'supposedly' works but she came home crying the other day saying she failed her gcse literature exam...
I pick a daisy outside my exam hall to calm my nerves down before an exam. I don't think it's lucky in any way, but it helps me to stay focused and serene.