To have your groff source be converted into slideshow-ready HTML, set the number register t2pslides to non-0 using the command-line option
This causes Troff2page to use the style sheet slide.css and JavaScript file slidy.js from Slidy to convert your document into a single HTML page that can be browsed as a slideshow. Troff2page looks for these files in the working directory, and if they’re not found there, it links them from the W3C website. It may be prudent to get these files beforehand and place them in your working directory, so the presentation doesn’t rely on WiFi.
A new slide is started for each level-1 section, i.e., .SH 1 and .NH 1. (Note of course that it doesn’t make sense to convert generic groff documents into presentations. The sections have got to be pretty short!)
An HTML page meant for presentation uses larger, bolder fonts by default (but you can add your own CSS). There are no navigation bars between slides.
Use the .pause macro to interrupt display of the rest of the current slide.
Consult the Slidy documentation for the keypresses and clicks you can use to progress through or dynamically alter the look of your presentation.