The Most Common Question

Taking pictures of oneself is often times how it begins, but the question I hear most often is: Who's taking the picture?
In the beginning, there was the 10 second dash. In my early days, that's how it was. I'd set up precarious arrangements of various household objects, in lieu of a tripod, set the timer, and make a break for it. Thankfully, Flickr is a wonderful teacher. Through the Project 365 group, I heard that remote triggers existed, and in various forms. They use infrared and a sensor on the camera itself, and they're inexpensive. I chose this little guy:

There you go, that's the trick. This little guy enables you to either push the button and instantly take a shot, or to give yourself 2 seconds of prep time before the shutter snaps. You don't have to worry about accidentally moving your camera, running back and forth, or having to drag a lackey along. There are a variety of types, this just happened to be the first I've found, and I like it.
Why is it never in the shot? It used to be.

Warmer (2009)

You can handle this is a few ways. You can drop/throw it (be careful with that though), stick it in your pocket quickly, 'shop it out, or just use slight of hand- which is what I do. You can pose in such a way where you can't see it, but you're still in character:

And it all falls apart (2014)

It's in my left (your right) hand, under that ribbon. That was a bit hard because I couldn't see, but that's also part of the fun.
This tiny thing gives you the freedom to take however many shots you want, without disturbing costumes/props/any setup, or making you run back and forth. They will have range limitations, and you can get more robust ones. Unless you're going quite a distance, it usually doesn't come into play; though you may look a little funny trying to line up the remote and the sensor just right.
That's all there really is to it! No man behind the curtain, just a teeny and handy bit of technology- readily available at your online superstore!