I'm no pro yet, and you'll have to excuse my description as it might not be as technical as you're used to. I had this same exact question though and can't remember if somebody here pointed me to the solution or if I found it through a google search. However, I'm grateful I found the method. I spent a quick two or three minutes searching for the same tutorial but to no avail.
http://photodoto.com/im-ready-for-my-closeup-6-methods-for-perfectly-focused-self-portraits/
That one is just as good I suppose, and the method I've adopted and have had great success with so far is method #5 - the flashlight (or any type of bright light you can shine towards the camera.) I don't always shoot in a dark room with a flash like the tutorial suggests, but I will dim the lights if necessary so the light I'm shining toward the camera is brighter than my ambient lighting. Then when I'm ready for the photo I'll flip the lights back on. This works best in manual mode and by taking a preliminary photo of just the background so that you can set the proper exposure, but there are probably some minute flaws with this method as the metering won't be exactly how you want it (you are on the other side of the camera after all.)
I set my camera up on a tripod, initiate a 10 second timer, and change the focus metering to "C-AF" (not exactly sure what the 'C' means and I don't have my manual) so it focuses automatically on the light I shine towards the camera (again I'm not too competent in explaining the technical reasoning for this or why it works but the quoted section below may give you an idea.)
Wikipedia.com said:
Contrast measurement is achieved by measuring contrast within a sensor field,
through the lens. The intensity difference between adjacent pixels of the sensor naturally increases with correct image focus. The optical system can thereby be adjusted until the maximum contrast is detected. In this method, AF does not involve actual distance measurement at all and is generally slower than phase detection systems, especially when operating under dim light. This is a common method in
video cameras and consumer-level
digital cameras that lack
shutters and reflex mirrors. Some
DSLRs (
Olympus E-420,
Panasonic L10) use this method when focusing in their
live-view modes.
Then I'll hold the light up near my eyes (or wherever you want the camera to focus), and press the shutter button down half way so it "locks" the focus into place. Then I press the shutter fully to start the timer and get into place.
The only problem I've had with this is I need to be within arms length to press the shutter button down (unless you have a remote shutter release), which I don't. Here is a poor quality example of me improvising with the glare of my watch from the sunlight coming in through the window. It was taken from my Myspace page, which means it's an extremely low quality image (damn them.) I'm at work, and have another example I can provide with much better quality if desired but hopefully this will provide a little help. My apologies again if my explanation isn't much help, it turned out longer than I actually anticipated coming into this thread. Good luck! :blushing: