Chill time is crucial for clean edges, so keep the second dough disk refrigerated while you roll the first, and pop cut shapes back into the fridge for 10 minutes if they warm up. Roll between two sheets of parchment to avoid adding too much extra flour, which can toughen the cookies. For softer cookies, bake just until the centers look set with no browning; for crisper edges, add 1–2 extra minutes. If the dough cracks while rolling, knead once or twice to smooth, but avoid overworking. Store undecorated cookies airtight for up to 5 days or freeze for 2 months; iced cookies should dry fully before layering with parchment. Adjust icing thickness by adding milk a teaspoon at a time for piping or dusting with powdered sugar for a quick finish.