How do people shave in the 24th century?

Question

Looking at the history of shaving, I just realized that modern shaving with razors, safety razors, double-blade safety razors, triple-blade safety razors, ... are all very recent. Which got me questioning, what advances have been made for shaving by the 24th century.

So, the question is, in the Star Trek universe, how do people shave? Is there any mention of how such personal grooming in done? I do remember Tuvok shaving with a futuristic looking straight-edge razor in "Year of Hell: Part I" when he has been blinded. But how do people normally shave?

In-universe answer or an out-of-universe explanation is fine.

Answer 1

With a (futuristic) razor

We see both Geordi LaForge and Ben Sisko using a similar-looking device to shave their beards and (in Sisko's case) heads:

The technology behind this device isn't explored on the show, but it doesn't appear to be bladed; presumably it uses sonic technology, or something similarly high-tech.

Though more traditional razors may also be employed

We do see Tuvok using a more traditional-looking straight razor, but given his character that may be more of a Vulcan tradition:

We also see Troi and Riker using an old-fashioned straight razor, suggesting that (as with many other aspects of 24th-century life) nostalgia for the 20th century is alive and well and living in Starfleet:

Answer 2

In some novels, beard repressors/suppressors prevent the need to shave at all

Several Star Trek novels (which the TV shows generally consider non-canon) include "beard repressor/suppressor", which is a substance that, if applied regularly, prevents the need to shave at all.

At that point [McCoy] noticed, to his disgust, that the brand of beard repressor he used had worn off: he had not kept track of the reapplication schedule. While the whiskers had not yet grown so long that they made him look even more dissolute, the stubble was scratchy and irritating. […]

McCoy washed, shaved, applied more whisker repressor, and put on clean clothes.

_{–The Entropy Effect, by Vonda N. McIntyre}

Kirk frowned, not because of the fact that he took the coffee black, but because filtered sunlight was glinting off golden-brown bristles on Riley's cheek. "Good Lord, man. Did you run out of beard suppressor?"

_{–The Lost Years, by J.M. Dillard}

Someone who applies this substance regularly may never have to shave for the rest of their life, thus making the question of how they shave a moot point.