How to exit self-timer mode on my Nikon D90?

Do I have to just turn the Nikon off or is there a button I have to press?

Added (1). You know, Jim A, I'm not as stupid as some of the other people, I just don't have the manual with me and I wanted a simple answer. I consider irony/sarcasm an inappropriate approach:/ but thanks, anyway.

It's the same button you used to turn the timer on…

See page 67

Turning off the camera will cancel the self-timer mode

Three steps.

Open the manual
read the manual
do what the manual tells you