Can you link where Reevy told you how to do this?
There are a couple different threads out there, but it is pretty simple. Here is my procedure:
1. Santize a mason jar (pint size, but size doesn't matter
) or erlemeyer flask as well as a 6"x6" piece of aluminum foil.
2. Brew up a starter (I boiled 2 cups of water and .5 cup DME), let it cool to room temp. Pour it in a mason jar.
3. Making sure it is settled and the yeast sediment is on the bottom, pour a 22 oz. Rogue brew into a glass (either Shakespeare Oatmeal Stout, Chocolate Stout or Brutal Bitter) but leave the last inch or so in the bottom of the bottle.
4. Swirl the Rogue bottle vigorously for about 15-20 seconds to dislodge all the stubborn yeast at the bottom of the bottle. Pour remaining beer/yeast into mason jar.
5. Cover opening to jar with sanitized foil.
6. Swirl up the contents of the jar every time you think about it/as often as you can to keep the yeast circulating.
7. As the yeast multiply you need to keep upping the amount of water/DME so they can continue to feed (and you can split the batch up). Then when it is time to pitch just pour out most of the starter fluid, shake her up and pour her into your wort.
You have to be VERY patient with it because the yeast is there, they just take a while to become noticable. The ideal method is to have an erlemeyer flash and and automatic stirrer, but since that wasn't and option for me i used the tin foil/ mason jar method