BIG tip here guys and gals....
VISIT A NATS CENTRE AND/OR TOWER ! ! !
The interview will go much better if you do, I promise you! Hint Hint!!!
Also, why would you NOT want to go for a visit??? How can you convince any interviewer that you're both serious and suitably informed about being an ATCO if you have nothing to base your opinion on? They WILL ask I assure you...