When I was at my friendly, local homebrew supply store recently, I was prepared to buy a yeast starter setup (i.e flask, DME, etc.), but the clerk talked me out of it. He suggested two things, first, that the yeast should acclimate to the kinds of sugars that they'll be fermenting in the beer (i.e. LME vs. DME) and, second, that an airlock will put pressure on the yeast by not evacuating the CO2 quickly enough. Admittedly, I'm a bit skeptical, but if his method saves me money, I'm going to give it a go.
- Activate yeast packet, and let sit for about 24 hours.
- Boil 1500 mL of water with 2/3 cup LME and one hop pellet.
- Cool wort in water bath to 70º.
- Poor wort into sanitized growler and aerate.
- Sanitize packet, and pitch yeast into growler.
- Seal loosely with a sanitized piece of aluminum foil.
- Let sit for one to three days or until a notable yeast cake flocculates at the bottom.