You are Immortal.

You have just discovered that you are Immortal. The simple kind, no having to repair any injuries, no aging just the best kind of immortality. What do you do first.
Myself, I go to the middle of London (my closest big city) and start to advertise the fact, jumping of buildings playing in traffic, all that stuff. Why? To see people react, do they call it a trick, am I heralded as the messiah or devil. How long before the government turns up. And if I am carted off so what. I just sit around for a century or two and then walk out of whatever ruin I'm in.