If you must.
Sabering Champagne has become fashionable, which is surprising for a custom that originally had its heyday among French cavalry officers during the Napoleonic wars (you’re on a horse; you want to open a bottle of bubbly; you are très chic; of course you use a sword).
In any case, given that saberage (as it’s termed) now is a thing, here’s a basic how-to for lopping off the top of a bottle of Champagne with a big frickin' knife. Do we suggest you do this? Not particularly. It can be quite dangerous; done improperly, the bottle can shatter, potentially slicing up your hands and at the very least startling the heck out of you. As with deep-frying turkeys—another somewhat mysterious current food trend—all it takes is a quick Google search to show the potential risks. (In case you’re still curious, though, even after all these warnings, watch this video for an amusingly unfortunate instance of how this classic and/or lunatic method of opening your fizz can go wrong.)
But if you’re dead set on sabering some Champagne (or if you're a reincarnated French cavalry officer), better that you know what you’re about than not. Watch the video below for a tutorial, and here's a rundown of the basic drill.
1. Procure a sword. Or very large, heavy knife. Very important note: You’re going to be using the dull back of the blade, not the sharp side.
2. Chill the bottle down as cold as possible. Use ice and water.
3. Remove the wire cage and find the vertical seam where the two halves of the bottle meet. Run your finger along it. Feel that? That’s the line you’re going to follow with the blade.
4. Is the bottle very cold? No? Bad idea. Chill it some more.
5. Point the bottle away from family, friends, pets, fish tanks, windows—anything that might be damaged by a high-speed flying nugget of glass and cork. Don’t point it at your face, either.
6. Run the sword swiftly and firmly (using the dull side, remember?) along the seam to the neck of the bottle, which, if all goes well, will pop right off.
7. See video above for clarification (note that the person in the video is using a specially made Champagne saber that is dull on both sides; should you wish to purchase a similar one, with a snappy zebu-horn handle, you can right here).