We can all agree that classic, sleek and shiny hair never goes out of style. While some days call for a wave or curl, we never cease to appreciate a fresh-pressed look. And because of that, we treasure our trusty flat irons - after all, they're usually responsible for our perfectly straight locks.

If you're like us, you've probably been straightening your hair since middle school, but are you getting the most out of your efforts? We compiled a list of the top six flat iron mistakes that could be keeping you from maximizing your straight 'do and protecting the overall health of your hair. Knowledge is power, right?

1. Not using protection. We're talking heat protection here. Use a product formulated to create a protective barrier against high temps for better results and less damage. You can opt for a leave-in treatment like Kérastase Nectar Thermique or a pre-styling serum like Pureology Strength Cure Fabulous Lengths to work into hair before taking an iron to it. Skipping this step means a fried (and often frizzy) end-result.

2. Styling your whole 'do with the flat iron. When you blow dry properly, it can be less damaging than a flat iron. After you wash, dry with a blow dryer pointed downward, and brush it straight. Once completely dry, use a flat iron on certain sections of the hair that could use a little sleeking up. Warning: Never try to straighten wet or damp hair - you'll do serious damage!

3. Utilizing that unnecessary max heat setting. No matter how fancy or expensive your straightener is, just because an iron can go over 400 degrees, doesn't mean it should. Studies show that you'll achieve the same results without the damage by using more moderate temps.

4. Letting it sizzle. Ah, the not-so-sweet smell of hair burning to a crisp! If you hear that sizzle, you could be doing a number of things wrong (two of which we discussed in No. 2 and 3 above). It could also be due to you holding the iron in place for too long. Instead of treating the straightening tool like a crimper, move it downward lightly, without pausing or pulling.

5. Not setting your style. Feel like your hair still isn't getting (or staying) straight? Instead of running the iron over it yet again, make sure you're finishing the job correctly. After straightening, apply a frizz-fighter (we love Redken Outshine 01 Anti-Frizz Polishing Milk) that will hold the style and add shine. For you curly-haired gals: Kiehl's Heat-Protective Silk-Straightening Cream can be applied before or after styling to achieve long-lasting results.

Have you made any of these flat iron mistakes? Let us know!

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