It’s a simple concept: only surround yourself with things you love.
For instance, I love this outfit.
One of the major principles of the KonMari Method is to go through everything you own and ask “Does it spark joy?” and if it doesn’t, get rid of it. Go with your gut and don’t rationalize. It really did make going through my clothes easy; I didn’t have to ask if I could make three outfits with an item or if I’d worn it within the past six months, I could ignore the rationalization that sometimes goes on in my head (people at work really like this skirt!), and just ask it I love it or not now. Not if I loved it before. So a few dresses I haven’t worn in ages stay. Anything I wore just because I felt I should or pieces I used to love but don’t anymore went.
But it’s much harder with other areas of the house. In the kitchen, do these oven mitts spark joy? Well, not really, but I need to have oven mitts. I don’t think it means I should throw them out and buy oven mitts I love (or should I?). In the bathroom, do I love this bottle of glasses lens cleaner? Does this nail file spark joy? Do I have strong feelings for this Revlon Pedi-Expert? (Actually I do, it’s essentially a cheese grater for your heels and it’s the best thing I’ve tried to deal with my terrible feet.)
So there’s stuff I love, and stuff I need. I don’t know if it’s possible to have 100% stuff I love. But 85-90% is probably ok, right?