My trick is to curl the hair from the top down, not from the bottom up. You'll need to use a traditional curling iron with a full clip. Take a one inch section of your hair and place the iron at the roots of your hair. Smooth the hair lightly with the iron and begin curling in the direction you want the hair to wave. I count to either 3 or 5 and release that section of hair. Move the iron down the section of hair and continue curling, holding the iron in place for only a few seconds. Do this until you reach the end of the hair, giving you a perfect Shirley Temple-like curl. Don't worry, it's supposed to look like that.
I like to cool curls with my blow dryer as I go to help them "set", which also stops my scalp from overheating. Once my entire head has been curled and cooled, I tousle the curls. For a more uniform wave, you can brush the curls with a soft-bristled brush or wide-toothed comb to release them a bit. After about a half an hour, the curls have released to the point where they stay for at least a day and a half, if not much longer. If you like, you can finish with a hair spray. I tend to avoid this, as I hate stiff, sticky hair. If I do use a hairspray, it's usually Suave Professional Touchable Style Hairspray.
If your hair needs a little boost, try adding mousse to your hair before you blow dry or some other setting lotion. I also get good results when I dry my hair using Living Proof's Prime Style Extender. Be sure to protect your hair with a heat protectant. I really like Got2B Guardian Angel 425 Heat Protectant (unless you are actually trying to cook your hair, you shouldn't need a temperature anywhere near that high. Especially not regularly). To finish my hair, adding volume and a little piecey-ness, I like Bumble and Bumble's Thickening Dryspun Finihsing Spray.
Below is a quick video that shows how I actually curl my hair, without sitting through the twenty minutes it actually takes me.
If you've tried curling your hair this way, let me know how it worked for you!
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