Start with Your Skin Type
What you want: a product that addresses your skin concerns
For Acne-Prone Skin
If blemishes are a problem, look for ingredients that keep pores clear, such as salicylic acid.
Clinique Acne Solutions Liquid Makeup, $25, clinique.com
For Full Coverage
A formula that does the job of several products -- primer, concealer, foundation, powder -- offers an efficient way to cover any flaws.
Stila One Step Makeup, $44, stilacosmetics.com
For Sensitive Skin
Mineral foundations, which can be powder or cream, generally have fewer fillers and preservatives.
Lancome Oscillation Power-foundation, $48, lancomeusa.com
For Aging Skin
Opt for creamy formulas with antiaging ingredients, such as sunscreen, hyaluronic acid (to reduce dryness), and collagen-boosting peptides.
Estee Lauder Resilience Lift Extreme with SPF 15, $37, esteelauder.com
For Oily Skin
Keep shine in check with ingredients that absorb oil, like silica.
CoverGirl Clean Oil Control, $6, drugstore.com
Pick a Color
What you want: coverage that matches your skin and leaves no makeup lines
Test It
Foundation looks different in the package than it does on skin, so trying on a sample is essential.
Give It Face Time
To test colors, apply different shades to your cheeks. Skin on hands and wrists has a different tone and texture.
Let It Dry
Allow liquid foundation to set before deciding on a color; the shade might shift a bit as it dries.
Seek Sunlight
Head to the store window and look at the foundation in daylight with a hand mirror. You'll be able to tell immediately if it looks natural on your skin.
What to use when you want a flawless finish, a custom blend, and a super-natural effect.

Best for Light Coverage
On the days when you want to get away with applying the bare minimum, tinted moisturizer is the way to go. It functions as your morning lotion but also has a hint of color to help balance skin tone.
Physicians Formula Healthy Wear has SPF 50 as well as licorice extract to help fade sun spots, $15, cvs.com
Best for Skin Conditions
For the touchiest skin, there's VMV Hypoallergenics. The foundations are free of potential irritants such as fragrance and dye. There are also formulas suitable for people with rosacea or very dry skin.
VMV Hypoallergenics Skin Savvy 60 is fragrance- and preservative-free, $50, vmvhypoallergenics.com
Guerlain Meteorites Perles Light-Diffusing Perfecting Primer, $66, sephora.com
MAC Mineralize SPF 15 Foundation is a creamy formula that comes in a compact and dries to a powdery finish, $32, maccosmetics.com

Best for a Close-Up
Look into almost any makeup artist's bag and you'll find a secret weapon: primer. The product lightly coats the skin, filling in imperfections and creating a smooth base for foundation to glide over. When applied to skin (after moisturizer and before foundation), it makes lines and pores fade away and helps makeup stay put longer.
The matte finish of L'Oreal Paris Studio Secrets Magic Perfecting Base is good for countering shine, $13, lorealparisusa.com
Martha's Pick
This primer is a new favorite of Martha's. "I have been using it every day," she says. She brought it with her on a recent trip to South Africa and also wears it while filming "The Martha Stewart Show." "It has gotten a great reaction," says makeup artist Charlie Green. The "pearls" of the primer are suspended in a clear serum; when the pump is pressed, the two combine.
Guerlain Meteorites Perles Light-Diffusing Perfecting Primer, $66, sephora.com
Best Replacement
If your favorite shade is discontinued, send a sample to Three Custom Color Specialists (threecustom.com). For $37, they'll match it.
Best for All Shades
If you have trouble finding a foundation that works with your tone, try the MAC counter, which has 50-plus tints to choose from. Odds are good that you'll meet your match.
MAC Mineralize SPF 15 Foundation is a creamy formula that comes in a compact and dries to a powdery finish, $32, maccosmetics.com
© 2013 Martha Stewart Living Omnimedia. All rights reserved.