Don't, it's stupid.

ARE YOU A STUPID CIVILIZATION THAT'S RUNNING OUT OF ENERGY? DO YOU WANT TO ENTER THE NEXT STAGE OF TECHNOLOGY? WELL, WE HAVE GOT THE SOLUTION FOR YOU!

INTRODUCING: THE DYSON SPHERE! THE DYSON SPHERE IS A MEGASTRUCTURE AROUND YOUR SUN THAT CAN COLLECT MOST OF IT'S ENERGY!

THIS PRODUCT IS AVAILABLE AT YOUR LOCAL SUPERMARKET FOR THE SMALL, SMALL PRICE OF... your entire solar system...

Okay, a Dyson sphere isn't easy or cheap to build, but it's worth it, right? Well, no.

First of all, it would just collapse into the sun and get destroyed. Second of all, there are much easier and cheaper ways to collect a lot of energy.

Dyson swarm

A Dyson swarm is another type of Dyson sphere. Instead of a sphere, we could build millions of satellites around the sun that would collect energy. That way, it wouldn't collapse into the sun and it would require less resources.

The coolest thing about building an energy collecting structure is that it would make us a type 2 civilisation. It's not like that would have any good use, but it sounds cool, right?

Black hole bomb

Finally, someting that doesn't have the word "Dyson" in it's name. A black hole bomb is a structure that doesn't harvest energy from a star, but from a black hole (or you could use it as a bomb, but i'll talk about that later).

But if nothing can escape a black hole, not even light itself, you shouldn't be able to harvest energy from it, right?

Well, this is how it works: First, you build a mirror wall around the black hole. Then, you shine a beam of light into the ergosphere. It will reflect and amplify the energy inside the black hole indefinitely.

If you want to collect the energy, you have to emove one of the mirrors. The energy will escape and then you can harvest it. But if you wait to long without removing the mirrors, everything will blow up.