With the White, establish the "white areas" of the eye. Follow that layer with a layer of Cream (PC 914), then White again, creating a buttery surface where additional layers will be easily blended. The white portions of the eye are rarely white, rather they're a mix of colors. Go back and forth, with darker and lighter values, building depth and adding shadows along with colors that add realism.
An application of Light Peach (PC 927) around the eye blended with Dark Umber and Cream further defines the rest of the eye. Now it's time to add color to the eyelid, using the White and Light Peach.
Continue layering the Light Peach with Dark Umber (PC 947) for the skin around the eye, including the eyelid and up into the eyebrow area.
Add in eyebrows and then eyelashes until the eye is complete.
The eyes are the gateway to the rest of the face, and will be what most people will immediately focus on. Take the time to draw them again and again. They will eventually become second nature.