How do you check your undertone in daylight?

[EmilyKi]

I'm trying to make a small wardrobe easier to combine, and I keep coming back to autumn colors. I don't want to buy a whole palette based on a quiz result. Several muted warm pieces seem easier for me to wear. That impression could be about personal taste rather than what suits my face, so I want to check it more carefully. A couple of neutral pieces and one accent might be enough for a trial. There are olive, tan, and terracotta pieces I can borrow or try on. I can compare them in natural light before spending money, ideally with the colors next to my face rather than laid out on a screen. A useful color should fit my existing outfits as well as look good alone. While researching what is my color palette I found several labels, but I would prefer a small real-world test over memorizing every category. Would you begin with neutrals or a more obvious accent? I can keep notes on how the colors look at different times of day. I'm hoping for a few reliable choices, not an entirely new closet. A practical result matters more to me than a precise season name. How would you test an autumn direction with just a few borrowed garments, and what would make you reconsider it?