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Even with all the celebrity inspiration, video tutorials, and top-of-the-line products out there geared toward helping you achieve those perfect, just-stepped-off-the-beach waves, it’s still—let’s be real—not always easy to use a curling iron. No matter what kind of iron you use, there’s some kind of learning curve that goes into figuring the right way to hold the barrel, how high to set the temperature, and how long to hold the hair in it—and that’s assuming you’ve got the best curling iron to start with.

So for everyone out there who feels more like an eighties prom queen than Blake Lively after they curl their hair, we asked Javan Stone, senior stylist at Spoke & Weal in Los Angeles, to help pinpoint what could be going wrong. Because sometimes the easiest way to learn how to do something is to learn what not to do. Here, his quick but effective rundown of curling iron red flags—all tailored for your hair type and the look you’re going for. Here’s to finally mastering how to curl your hair, once and for all.

Mistake #1: Assuming that a bigger iron = better beach waves

People often think the bigger the curling iron, the beachier the waves. Not true. “If the iron is too big for your hair length, it’s just going to be a pain to use,” says Stone. You can always brush through tighter curls to make them relax.

Mistake #2: Saving hairspray for the very end

If you only spritz when you’re done, you’ll run more of a risk that your hair will fall flat. “Spray your hair with a light- to firm-hold hairspray like Aveda Air Spray or Control Force to prep it, and also while you set your curls,” Stone says. “This is especially important if your hair is resistant to curls.” Also, steer clear of hair oil. It’ll weigh down your waves.

Mistake #3: Using the wrong heat setting for your hair type

“If you have processed hair, keep the heat a little lower, but if you have healthy hair, feel free to turn it up,” says Stone. “The hotter the temperature, the better it’ll set your hair.” But proceed with caution: Use a heat protectant.

Mistake #4: Not using different wrapping techniques

This might seem like a no-brainer, but different types of waves and curls require you to wrap your hair around the barrel differently. “If you want an old-school glamour curl, you want all your hair around the barrel,” Stone explains. “If you want modern, messier waves, leave the ends out and start lower down on your head.” This is also where an iron with a clip can come in handy (to help hold the ends in), whereas a rod iron will help to keep the ends out and loose. (For more on messy waves, read our how-to here.)

Mistake #5: Not paying attention to the angle at which you’re holding the iron while you curl

“If you want more volume, heat the root of your hair first and hold the iron perpendicular to the section—i.e., at a right angle—you’re curling,” Stone says. It should be straight off your head. “If you don’t want volume, hold the iron straight down instead.”

Mistake #6: Holding the iron on your hair way too long

Drill it into your brain: You should hold an iron on your hair for eight to 10 seconds max. “You can hold it a little bit longer if your hair is resistant to curls or you want a tighter wave,” Stone says. And make sure to hold each curl for a consistent amount of time. “Holding each section for a different amount of time or starting before the iron is hot enough will mess with the outcome,” he adds.

Mistake #7: Not blow-drying your hair all the way before you curl your hair

Ever put an iron on your hair and hear it start to sizzle? Yeah, not good. That’s what happens when your hair is still slightly damp. “Starting with a good blow-dry takes time, but you’ll get salon results if you do it that way,” Stone says. “Prep your hair before you blow-dry with a heat protectant and a hold product, then spray it with hairspray before you start curling.” Not only will it keep your hair from frying, but it’ll help set the curl better.