when you hear freddy laugh (in total she will laugh 4-5 times!) each laugh is when she will move, the first laugh is cam 7, then the 2nd she will be in cam 1B after that, the 3rd laugh will send her to cam 5! then she will go cam 3 and will stay there for a while, then the 5th laugh she will be on cam 6! where she can attack you .
also each laugh is close to a new hour so use that to know when your close to the next hour.
hope that helps ^^