I was watching tennis on television and what struck me, aside from their intense playing styles, was how great Serena and Venus Williams's makeup looked on court. How do they keep it on through all that vigorous exercise?

Being in the spotlight has its drawbacks ‑- the incongruity of playing a hard physical sport while wearing makeup is one of them. But as celebrity performers whose radiantly expressive faces grace the pages of newspapers, television and magazines worldwide, they want to look their best. Happily, I was able to consult with Kym Lee, Serena's personal makeup artist and founder of Outer Skinz Image Group, who shared some of her favorite products and sweat-proofing tips. (To arrange a consultation with Kym Lee, whose home base is Washington, D.C., call 301-306-SKNZ (7569). Here's how to prepare your makeup to withstand the most extreme physical exercise.

• Cleanse your face thoroughly with an antibacterial face wash designed to rid the skin of excess oils.
• With a sterile cotton ball, dab face with an astringent containing ingredients such as lemon and burdock root, which work to naturally absorb oils.
• Then apply a lightweight moisturizing lotion. You may want to skip the traditional T-zone, or other areas where your skin naturally becomes oily.
• With your fingers, spread a small amount of long-wearing tinted moisturizer evenly over your entire face, ideally one that contains an SPF of at least 15.
• Apply an opaque foundation directly to any overt "imperfections" such as under-eye darkness, redness or acne scars. It helps to start with just a miniscule amount, warmed between your thumb and forefinger, placed on the skin with soft, dab-patting motions.
• Next, for a smooth, unified blend, use a non-latex makeup sponge to really press the foundation against skin. Remember, you don't want to rub as much as you want to press to ensure that the cream has solid contact with skin.
• Set the foundation with a translucent, loose powder, which you'll apply with a wide, flat, velveteen puff, again using firm pressing motions. Wait three minutes and apply powder again.
• Add a tawny shimmer to the eyelids using a flat, firm-haired eye-shadow brush, so as to keep the color concentrated.
• Mascara is next and it's got to be waterproof and non-splattering! Apply two coats to the upper lashes in even, controlled strokes.
• And last, for lips, try a sheer copper gloss, which will give lips just a hint of gleam, while keeping them lubricated.