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Smooth, sexy starlet hair

In the late '90s, Aniston switched from The Rachel to this super-sleek, glamazon 'do. "This is when everyone started to flat iron their hair like crazy," Decuers says. It would still look great now -- the key is lots of shine.

Step 1: Minimal layering means straighter hair, and more shine. That's because light bounces off a flat surface better than a wavy or curly one. (Aniston's cut is basically one length, with layered ends.)
Step 2: Use a shine serum, not a spray. Try Barex Tricolife Serum, $27.50. Serums tend to have more silicone, and offer more gleam, Decuers says.
Step 3: Squirt the serum onto your palms, and then run your hands down your hair, over and over, like you're milking a cow (weird imagery we know, but it seriously works). It coaxes hair even straighter.