You can do easy root touch-ups at home, but "when you're making a big shade change, like brunette to blonde, there's no substitute for the salon," says Aura Friedman, a Wella colorist who routinely helps M.I.A. switch shades.
Cuts: Investing in a great haircut that grows out without losing its shape can mean less time and money spent on products and maintenance. Keep in mind that "regular trims are imperative for women with finer hair to prevent split ends and limp strands," says San Diego salon owner Jet Rhys.
Highlights and Lowlights: Strategically placed color will grow in better, meaning fewer touch-ups. "For fall, I prefer to paint deeper tones on the underside of hair so that it looks natural as it grows out," says Friedman. "Or if you love a celebrity's hair in a photo, only a professional colorist will know where to apply highlights and lowlights. You can't get that from a box."
Bang Trims: "Blowdry your bangs as you would normally, twist hair in 2-inch sections, and snip the ends until you've reached your desired length," says Rhys.
Maintenance: "If you take care of your hair health, you can go longer between salon visits," says Rhys. Fine or color-treated hair types should use gentle, sulfate-free shampoos. Medium to thick hair needs moisturizing ingredients like glycerin and proteins.
MC RECOMMENDS: Pantene Beautiful Lengths Replenishing Mask, $5; Avon Advance Techniques Color Protection Lock-In Treatment, $8; L'Oréal Paris Ever Strong Bodify Shampoo, $7; TRESemmé Naturals Radiant Volume Conditioner, $5.
Face time with your dermatologist or aesthetician means money well spent. "The skin cycles once every 28 days, leaving complexion-dulling dead cells in its wake," says Chicago-based dermatologist Dr. Carolyn Jacob. "Monthly dermabrasion or facial appointments are ideal to slough away the cells and keep the skin looking as fresh as possible." If monthly appointments are too much of a commitment, "going once every two to three months also has benefits," she adds.
New Skincare Advances:
As for at-home products, growth-factor-rich eye creams and moisturizers are expensive but can be beneficial for reversing the signs of aging in post-20s skin.
Jacob recommends investing in pharmaceutical-grade omega-3 fish-oil gel caps and vitamin D supplements. "These strengthen the skin and promote better internal health, too," Jacob explains.
"I don't think you have to buy fancy products," says dermatologist Dr. Debra Jaliman. "Use the money you save to treat yourself to a treatment or filler." In particular, she recommends buying inexpensive cleanser because it spends very little time on your skin before it washes down the drain. "I put my cheapo cleanser in a crystal pump so it looks beautiful."
MC RECOMMENDS: Skin Effects by Dr. Jeffrey Dover Glycolic Cream Cleanser, $13.
At drugstores, look for proven ingredients like retinol, antioxidants, salicylic acid, niacinamide, soy, and sunscreen with UVA/UVB coverage.
MC RECOMMENDS: Advanced Home Actives Brazilian Peel, $78 for set of four.
Fancy Face Oils:
We found skin-plumping, ultra-nourishing power in these under-$40 bottles.
MC RECOMMENDS: Kaé Vitality Day Serum With Rose, $38; Melvita Calendula Oil, $19; Pratima Kapha Essential Oil for Oily Skin, $34.
If you're going to drop some dough on new makeup, plan on spending your money strategically—investing in great foundation, primer product, and tools can actually save you money and time in the long run because you'll find you don't need as much other makeup. "People use the wrong basics, and then they pile on other makeup trying to find balance," explains NYC makeup artist Rebecca Restrepo. "Your foundation shade needs to be perfect."
MC RECOMMENDS: Yves Saint Laurent Teint Radiance Radiance-Enhancing Flawless Foundation SPF 20, $55; Shiseido Pore Smoothing Corrector, $30; Chanel Natural Finish Pressed Powder in Beige Clair, $44.
Tools: High-quality makeup brushes can be pricey, but, as Los Angeles—based makeup artist Sarah Lucero points out, "You can extend the use of your foundation by applying it with a pro foundation brush—it will create an airbrushed look, and you'll use less product than if you used your fingers." Cleaning your brushes once a month will help them last a long time—Restrepo recommends washing them with dishwashing soap, then air-drying the bristles by letting the ends hang off a table.
MC RECOMMENDS: Sephora Blending Makeup Brush 237, $24.
Mascara: "With mascara, it's easy to find great formulas that you can get away with buying at the drugstore," says Lucero. She also points out that since you're supposed to toss your tube every two to three months, cheapie mascaras won't put as big a dent in your wallet.
MC RECOMMENDS: Rimmel London Volume Flash Bold Curves Mascara in Black, $7.
Trendy Colors: "For bright, fun makeup, mass-market companies have great colors," explains Restrepo. For instance, "CoverGirl's Liquiline is genius. It has the ease of a pencil with the drama and staying power of a liquid." And go ahead and experiment with this fall's in-your-face lip colors—you won't feel guilty when you use that $5 fuchsia lipstick only three times.
MC RECOMMENDS: Topshop Lip Stick in Rosa, $14; CoverGirl LiquilineBlast Eye Liner in Violet Voltage, $8; Revlon ColorStay 12 Hour Eye Shadow in Silver Fox, $7; Sinful Colors Nail Polish in Fiji, $3; New York Color Rose Lip Gloss in Peony Kiss, $3.