Curling iron or Curlers?

I have naturally, very thick curly hair. Whenever I curl my hair, it puffs up. I do not have curlers yet ( going to get some tomorrow) and i was wondering if it was going to look the same? I want a nice, natural looking curls ( even though i have curls, i want them to look professinal and no-frizz.) In your personal expeirence, which one would be better?