Start by looking for ingredients you already know your skin tolerates. Product labels usually list ingredients from highest to lowest concentration, though ingredients present in small amounts may appear in a different order near the end.
Look at the whole formula rather than expecting one ingredient to tell the entire story. Texture, fragrance, and the way a product is designed to be used can all shape your experience.
When trying something new, patch test first and introduce just one new product at a time. That makes it easier to notice what feels good for your skin.