Ferment at 50°F (10°C) until final gravity is reached; increase the temperature by a few degrees at the latter stages of fermentation to aid in diacetyl cleanup. Once the beer completes fermentation, but before packaging, you may want to cold crash it to 35°F (2°C) for 48 hours to improve clarity. Bottle or keg the beer and carbonate to approximately 2.5 volumes. Store carbonated beer at near-freezing temperatures for at least 4 weeks before drinking.

Lagers take longer to ferment than ales do. Ideally, you would do a diacetyl rest when fermentation is approximately 75% complete. A diacetyl rest is nothing more than allowing the fermenting beer to warm up to room temperature for 3-4 days...it gives the yeast a chance to consume the diacetyl that was created during fermentation. At any rate, a general rule of thumb is to let a lager ferment for 10 days, then diacetyl rest for 3-4 days. I personally transfer to secondary at this point but others don't transfer at all. Then cool to lager temps (32-40 degrees F) and leave it for 4-6 weeks.

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6 days @ 50F
5 days @ 54F
2 weeks @ 66F (includes diacetyl rest + warm conditioning + carbonation time)
Lager for 2 months @ 35F