This one is as simple as it gets. Boil your water in a pot, and let it cool down. When you do this, the calcium and magnesium form little hard lumps that settle at the bottom. That’s the mineral party, officially over.
You pour the top water off carefully, and boom—softer water. It’s like skimming the cream off the top of milk, but less yummy. Pro tip: don’t let the pan boil dry. You’ll be left with a layer of mineral crust that’s harder to scrub than a burnt lasagna.
This works great for drinking water, but don’t try it for your whole shower. You’d need a bathtub-sized pot and a very patient spouse.