Ask HN: What is the best way to learn how to design experiments?

I don't have a background in science, math, or statistics.

I'd like to learn how to create experiments to test ideas in my business like doing x leads to y increase in sales.

Does anyone have books or resources that they could recommend on how to design business experiments that have good logic and are as data-backed as academic research? There are a lot of variables in my business so I'd like to avoid confusing correlation with causation, learn how to create a proper control group, and more.

For more context, I'm starting to get into machine learning and deep learning through fast.ai. What should I learn or be aware of as I move forward that is complementary or essential to machine learning?