Beauty products for a Sagittarius tend to be minimal at best. And the products you do use need to honor and support the Earth itself. That means buying natural cosmetics or even making your own.
Like actress Lucy Liu, the epitome of your sign's natural beauty, other than a little sunscreen or tinted moisturizer, you're generally makeup-free, unless attending a special event, or maybe going out on a date.
If you want to try a little more makeup, and step outside your comfort zone, look into product lines that feature natural and organic ingredients. You can multi-task, and get some of your nutritional needs met by what you put on your face and body - think nut oils, aloe, minerals.