I have been doing makeup for 27 years skin tones are all brown, light beige's to dark browns. The only people that have ruddy undertones are; native Americans and some people of Scottish decent,ruddy undertones are very rare, however many people mistake rosy cheeks for ruddy skin tones.
Most people are beige,beige yellow or yellow beige. When you wear foundations do they turn yellow to orange on you? then you are more beige. Women with darker color skin will have yellow as the dominate color where paler skin would be beige to beige yellow.
Test the product on your jaw to neck, for pale skin and on the apple of the cheek if the skin is darker. Squint, look in the mirror and use the color you don't see, however you should do this in day light, because when light is around 5600 k you will see a more accurate color.