Actually I should mentioned this.
Flashing is "Window Flashing provides an inexpensive and easy to install method of stopping water penetration behind siding" from: http://www.tamlyn.com
When you go to the hardware store, it actually comes with silver, then different colors,that which is the color that shows around you windows ( white, brown). It cost me about $5.00 for 2 feet.
I noticed that some people make really big ones (well buy I imagine) and put them on their wall, it would be so much cheaper to make them, and then look amazing about a fire place all year round.
What I did was spray it with gold paint then put a clear coat on top of that.
I suggest if anyone makes these, buy the smallest metal snips you can get. Its worth it, then just use a utility knife to do the slits, and dont push hard, or else it will make you have a star in many peices lol
Good Luck if you have anymore questions feel free to ask.