The beauty of the serum is that you can customize how much hydration you give your skin every day. I suggest starting with one pump and build or decrease from there. In the evening I use more, in the morning I useless. If I’ve been a good girl, I'm well hydrated and have eaten clean, whole foods (complete with my daily “insurance policy” green drink) — I don’t need as much as on the days that I barely have a drop of water (coffee does not count) and have eaten on the go. Those days I need a little extra. I also think your age will dictate how much serum you use as the skin’s natural oil production decreases over time. For instance, Lisa is 10 years older than Kari and uses double the amount of serum (day and night). Younger women may use even less. The beauty of pure product is you get to customize your level of hydration every day.