To find your foundation determine the strongest underlying tone.
Determine undertones
Find your foundation shade/tone
Shop
Warm red and copper undertones shop: Sahara, Cacao, Mocha, Bronze, Coffee, Mahogany, Sienna, Chai, Porcelain in normal skin foundation and N series in oily skin foundation.
Cool yellow and gold undertones shop: Sunset, Cinnamon, Caramel, Expresso, Salem and Ivory in normal skin foundation and C series in oily skin foundation