Unknown. But the Taboo probably works in a similar way to the Trace.
The spell that the Death Eaters/Snatchers use to enforce the Taboo isn't specified in the books. So there's no one-word answer to this question. However, it's worth noting that Voldemort's name only became Taboo after the Ministry of Magic fell to the Death Eaters. If they could've created the Taboo beforehand then I think they would have done so. The apparatus of the Ministry was required for them to enforce the Taboo.
The Taboo works, I think, a bit like the Trace (which monitors the unlawful use of magic in underage children). This allowed the Ministry to know where and when a child performed a spell (although not who actually did the magic...) pretty-much instantaneously. Harry apparently got his owls from the Ministry reprimanding him for his use of magic within minutes of the Trace being activated.
Dear Mr Potter,
We have received intelligence that a Hover Charm was used at your place of residence this evening at twelve minutes past nine.
As you know, underage wizards are not permitted to perform spells outside school, and further spellwork on your part may lead to expulsion from said school (Decree for the Reasonable Restriction of Underage sorcery, 1875, Paragraph C).
(Chamber of Secrets, Chapter 2, Dobby's Warning).
Of course, the spell which powers the Trace isn't explained either. I'm guessing that having access to a Ministry of Magic list of trained witches and wizards doesn't hurt. However they work, both the Trace and the Taboo use the Ministry of Magic apparatus to detect things being done by the wizarding population. Indeed, the two have been confused in canon. In Deathly Hallows the trio are found with the Taboo but think that the Death Eaters may have used the Trace.
She turned to Harry.
"You - you don't think you've still got your Trace on you, do you, Harry?"
"He can't have," said Ron. "The Trace breaks at seventeen, that's wizarding law, you can't put it on an adult."
(Deathly Hallows, Chapter 9, A Place to Hide).
My best guess would be they use some kind of tracking spell. We don't see this in canon but it fits with the results the spell produces.
Now they've put a Taboo on it, anyone who says it is trackable -- quick and easy way to find Order members!
(Deathly Hallows, Chapter 20, Xenophilius Lovegood).
It should be noted that magic that works this way but which isn't fully explained isn't unheard of in Harry Potter. The Dark Mark works similarly. Voldemort can press his Mark and all Death Eaters Apparate to his location, even if they don't know where he is.
Every Death Eater had the sign burnt into him by the Dark Lord. It was a means of distinguishing each other, and his means of summoning us to him. When he touched the Mark of any Death Eater, we were to Disapparate, and Apparate, instantly, at his side.
(Goblet of Fire, Chapter 36, The Parting of the Ways).
Similarly, when a Death Eater presses their Mark Voldemort knows which Death Eater has pressed the Mark and is able to find them - even though there are Death Eaters scattered here, there and everywhere. How Voldemort and his gang are able to do this is never explained.