Thinking of the sword plant like a perennial plant growing in my garden i'd cut the oldest leaves first. they're the outer most leaves, it even looks like some are starting decay. The plant grows from the center so leave those as much as possible.
You could peel it like some have suggested but that will set it back (which might be a good thing)
you could even cut the leaves in half but that wont look that good.
For my swords I do what all these guy's have said. My method for cutting is to take sharp stainless scissors , push them under substrate where they need to be cut and snip. I don't know of any benefit to this I just don't like seeing the cut off area's