How do you set the timer on Candy FL-134XUK? ?

Set timer according to instruction manual but when i set the desired temperature the oven came on immediately rather than waiting for the time i'd set?
What did i do wrong?
I set the amount time it needed to be on for, then the time the oven needed to switch itself off, then turned the dial for the temperature and the oven came on?? surely it shouldn't?
Help?