Whether you call it speculative fiction, science fiction, fantasy, or some other term, one thing all these genres have in common is exaggeration.
In Atwood's fiction, she takes certain traits of people, society, nature... and blows it up beyond real life. You end up with gene splicing run amok, super hippies, and Handmaids. In The Year of the Flood, there's even Painball. The best way to describe Painball is by reminding you of the idea of Roman gladiators duking it out in the arena. Switch it to contestants who are exclusively criminals and a no-holds-barred, out-for-eviseration, setting and you have Painball.
This week, I challenge you to exaggerate. Let's do some world building. Think of an aspect of modern society that gets on your nerves (road rage, political extremists, people who say they are allergic to certain foods, but who are really just picky eaters). Now, list out all the details you can think of about that thing. Pick an aspect or two and exaggerate. You have a society where this one thing is a key part of the culture/politics/daily life. What happens when the whole country revolves around road rage?
Write it out. Don't just make it big, make it larger than life. There's your world.