Princess Diana famously used Max Factor's Sheer Genius Foundation. This foundation was known for its sheer coverage, giving a natural, fresh look. While this particular foundation is no longer produced, it was a key component of her signature makeup look, particularly for her engagement photo shoot. No longer available, an alternative recommended by Make-up artist Clayton Howard, who personally styled her first 1980 Vogue shoot and engagement photo, is the Max Factor Miracle Second Skin Foundation SPF 20 - Light Medium Foundation Women. So light, so lovely. Perfect for peaches and cream skin, just like Diana.
To layer with the delicate Max Factor, consider the Yves Saint Laurent - 'Fusion Ink' liquid foundation 25ml B10, an actual Diana product that she used and loved. Pretty, subtle, and refined.