挑选一个新鲜的南瓜。 雕刻前先把南瓜清洗干净，目的是清洗南瓜上可能有的细菌。 将南瓜内部的肉和瓤挖干净，这些部分也是最容易长霉菌和腐烂的。

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Before you begin to carve your pumpkin, make sure the stem is thick and strong and that the skin is not punctured. Broken skin allows bacteria an entry point, which speeds decay. If the pumpkin is already a little soft in the pumpkin patch, even in a tiny area, it's well on its way to rotting. That small soft spot will be a caved in pumpkin in a matter of days. You want a pumpkin with a nice hard body, no give when you press it gently, and even color. This helps prevent bacteria from entering before you've finished carving. Gently wash the outside of the pumpkin with lukewarm soapy water, and ensure that your carving tools are clean. This will remove all of the gooey parts that are prone to mold and decay. Using tools sold specifically for pumpkin-carving won't necessarily extend the life of your pumpkin, but tools that are very sharp will create cleaner cuts that will help it last longer. Ragged edges provide more surface area for decay-causing bacteria to settle in, and too much unnecessary sawing will bruise and soften the pumpkin. The thickness of the pumpkin will not greatly alter how quickly it rots. If you scoop away too much by accident, don't fret.