Tubes and pipes and copper windings and cables. It's not as if your reactor exists. So just make it stylish as you like. If you like kraken or snakes, make the cables snaking in and out. If you like steampunk, make brass tubes. If you like stinky diesel engines and spidery moving limb parts, make a V8. If you go all singularity sci fi, make it look like a small box in the cupboard.
I guess this question is as open as it can be, because it is purely taste based.
You won't see the actual working components under layers of isolation against heat and radiation. What you can see are the tubes and pipes going in and out through the isolation wall, and there are many of them because an actual working design would have an energy density which would be crazy. Compared to a V8, which you can see because the temperatures involved are not high, just think that you need to isolate and guide hard radiation into your converter and that plasma temperatures are like 10 million degrees, so you need active casing. And that's what you will see, and those you can design as you like.
https://de.m.wikipedia.org/wiki/Wendelstein_7-X
The general reactor chamber is either a ring (tokamak, stellerator), or a ball (laser fusion, condensed tokamak). Out from there you have x-ray collectors which work like solar cells on high energy, in many layers. For the ions and electrons you have a tunnel going out from the core, which is tasked to capture first the motion energy then the ion itself for energy production. That laser fusion thing may also have a magnetic piston, not with mechanical moving parts but with the same working principle. To capture neutrons, you have a layer of material inside the reactor which then degrades into new fuel.
So. Looks like a 50 meter hairdryer with thousands of (your design choice) either cables or pipes or both going in and out.