Before you say it, I did a search and found the following answer from six years ago, which doesn't work:
"Press menu
use the multi selelctor to get to teh custom shooting menu it will look like pencil icon
press the multiseelector right
use the down mulyiselector to get to menu custon settings 11
press OK or the right selector again
select self timer
press OK
Now the fn button is set to the self timer, you press the fn button and it will activate it then press the shutter release to activate it "
I have done all of this. I press "Fn" and it says "Self-timer" on the display screen. I press the shutter button, and it doesn't do anything. There is no countdown, there is nothing on the display to indicate that it might or might not be doing anything.
Twice, out of about 20 tries, it did actually work. Naturally it never worked when I actually had my shot set up, and most of the time it never worked when I was just testing it either.
What's the magic formula that makes it work?
Read more: How to set the timer on a Nikon D60?