- Choose two things. I like going with two colors but they can be anything. Two colors, two color schemes, two textures, two symbols, two songs. If they are visual, but formless, like colors, imagine or even draw them as yin and yang, or some other clear depiction of dichotomy.
- Assign each of them to another thing. These can also be whatever. Elements, categories, concepts, anything you’d like. If you’re drawing this out, label your two things appropriately.
- Justify how your two things are opposites. Be as profound about it as you want. Stretch your logic as thin as you have to. Good luck.
- Think about the potentially strange system you’ve come up with. How much sense does it make? Does anything lie outside of it? The way that something “falls into” either of your categories doesn’t have to be literal.
If you want, you can collaborate with someone else on any of these steps. For example, you can come up with one color, and ask a friend for the second. You can do this without telling them what it’s for or even what your pick is for added challenge.