Not sure how else to explain this one because it doesn’t always come up in a story. You might not have to design anything new for your world. Then again, you might have to come up with something since a modern device makes no sense for the cultures and tech that you already have. Can’t have a toilet without indoor plumbing after all. Well, you could if you tweaked things. Still, it’s best to have some kind of plan and that isn’t easy even with gnomes.
- Consider your starting technology level before you settle on an idea. If you’re sticking with strict medieval European standards then you aren’t going to be moving far away from those. This is because of the mindset of those who live in your world. They won’t jump from water wheels to nuclear fusion. Advancements need to be logical and not leap too far ahead of what already exists.
- The inventor can be a crazy outcast since they’re trying to introduce a life changing device or concept. At least, people will think they’re insane. This is only if inventors are rare too. If there’s an entire culture built around advancing technology then people won’t be too shaken. Still, you can’t have them accept these things right away too because change is scary. Find that balance between caution and acceptance that will fit with your world. Also, not every inventor needs Einstein hair and the hygiene of a teenager who thinks deodorant once a week is getting the job done.
- You don’t have to make your fictional inventions identical to something we can find in our world. The needs and resources might be different in your world, so a variation can be created. For example, the addition of magic can be used to design refrigerators without the cooling technology of Earth. Look at what you have and see where you can go with it. Also, why does it go from refrigerator to fridge? Where does the ‘d’ come from?
- Having a culture that is more advanced and creates new technology can help, but it doesn’t always work. They have to be willing and able to share what they’ve created. If they are making things that only work in their kingdom then it won’t be found in other regions. Maybe they fear neighbors becoming their equals and want to retain items that give them an edge. It would be a localized advancement. This is why I had the gnomes of Windemere spread out and happy to share. It explains why things like indoor plumbing are becoming more common worldwide instead of solely in gnome cities.
- Not every invention you introduce has to be geared towards battle, adventuring, travel, and medicine. There is nothing wrong with introducing advancements in clothing, entertainment, or food. These are important aspects of culture, which we don’t always look at as places where inventing can occur. Yet, they can be advanced with new materials.
- Explosions are fun when showing inventors, but they aren’t necessary . . . They are really fun to write though.
- Inventions don’t always have to work perfectly. Prototypes can be used by heroes, which means things can go wrong. We have things break all the time in our world, so why not in fiction? This means that they can be seen as unreliable items, which are a source of story suspense. It really works if they invention has already acted up or failed once, but they’re still trying.