Since powder is the top-up, your morning base matters more. A tinted moisturizer with SPF gives you light coverage and a real layer of sunscreen in one step, which is the easiest way to make sure you are protected before you even think about reapplying.

NARS's Pure Radiant Tinted Moisturizer is SPF 30 with vitamin C, hydrating and brightening. Tarte's BB Blur is a matte tinted moisturizer with SPF 30, lovely on oily skin that shines by noon. Tower 28's SunnyDays is a 100 percent mineral SPF 30 skin tint with light to medium coverage and no pore-clogging ingredients, a good pick for sensitive skin.

Dr. Jart+'s Premium BB is a Korean BB cream with SPF 30 that hydrates and conceals for a natural glow. Fenty Beauty's Hydra Vizor Huez is a mineral SPF 30 tinted moisturizer in ten shades that visibly reduces the look of pores.

And bareMinerals' Original Loose Powder Foundation, SPF 15, is one of the original loose mineral foundations. It is lovely on top of a tinted moisturizer for more coverage, but SPF 15 on its own is below the SPF 30 that dermatologists recommend for daily wear, so wear a sunscreen underneath.

Use about a quarter teaspoon for your face, which is more than most of us use. That is the amount that gets you close to the protection on the label, and it is why a tinted formula you enjoy wearing makes such a difference.

Some days a powder is not the right tool. Sunscreen sticks are the easiest way to reapply on bare skin or over light makeup, and they are the ones I keep in my bag for the beach, weekend sports and long walks.

Shiseido's Ultimate Sun Protector Clear Stick is SPF 60+, invisible and made for active days. Dr. Jart+'s Every Sun Day stick is SPF 40 with a matte, invisible finish that blurs pores. Kiehl's Better Screen UV stick is SPF 50+ and helps correct the look of dullness and uneven tone. EADEM's Sunsuede stick is SPF 50+ and doubles as a blurring primer, soft matte and shine controlling.

For glow, Glow Recipe's Watermelon Glow stick is SPF 45 with niacinamide and hyaluronic acid. Belif's Aqua Bomb Sunstick is SPF 50+, a clear gel that glides on for quick touch-ups. And Supergoop's Glow Stick is SPF 50 with a glowy finish that doubles as a highlighter on cheekbones.

If you wear full makeup and hate touching your face, ONE/SIZE's On 'Til Dawn setting spray has SPF 28 and locks makeup in place for up to 16 hours. Like powder, a spray is a top-up, since it is hard to know how much you are getting, but it is far better than nothing on a long day.

Glide a stick back and forth several times over each area. One swipe leaves too thin a layer to protect well, so think of it as coloring in rather than drawing a line.

Here is how it fits together. In the morning, a cream sunscreen or an SPF 30 tinted moisturizer, applied generously. At lunch, or after two hours outdoors, a few passes of powder over your makeup. On a sporty or beach day, a stick for your face and a cream for everything else, reapplied after swimming or sweating.

Powder also works on your part, your ears and the back of your neck, the places most of us forget. If your skin is fair or burns easily, reapply more often and add a hat on bright days. Keep one powder in your bag and one at your desk. The best sunscreen is the one you will actually reapply. If you want to keep browsing, I also put together Naked Sundays and Best Clean Sunscreen for Face That Does Not Pill Under Makeup.