-Pyralux, AKA copper-clad kapton. I got mine from DuPont- I wrote them saying I was a researcher and they sent me a bunch. Maybe you'll have the same luck; otherwise eBay works.
-Ferric Chloride or other etchant (this is writing assuming you're using Ferric chloride- still conveniently sold at Radio Shack)
-Laser printer or copier
-some sort of graphics program
-nitrile or latex gloves
-SMD parts (these do not work with through hole components)
Step 1: First, Prepare Your File in AI (or Any Other Graphics Program)
Step 2: Prepare Your Pyralux
To prepare your pyralux, first take some rubbing alcohol and rub down the copper side. You must remove all thumbprints and hand oils. Once you've done that, take your brillo pad, and gently but firmly scuff the entire copper side. The pressure should be enough that you see the copper being marked, but not enough to crinkle it. Don't crinkle it.
Once more, wipe down with the alcohol to remove the copper dust you just created. Wipe with a paper towel. set aside and DO NOT TOUCH AGAIN WITH BARE HANDS. From now until after you develop, don't touch it. Just...don't.
Step 3: Print!
If you're on a copier, set the print to extra dark. Lots of toner= better resistive in the etching stage.
Hit go, or copy, or EXECUTE or whatever.
Do a little dance (with your gloves on!) continue to try to not get kicked out of Kinko's.
When it comes out the other side..take it out (with your gloves on!) and place it in a bag if you're in good 'ol Kinkos, or just asside if you're abusing your own printer.
Step 4: Etch!
be sure to properly dispose of your Ferric Chloride.
Step 5: Kabloomers! You Have Boards!
I originally wrote this up for Steampunkworkshop.com. Check it out and other stuff I did/do over there!