DO NOT use the marcels unless you know what you're doing. I've been pressing my own since I was 15 (16 years ago) and it's still tricky for me sometimes. You have to make sure you monitor the heat closely, otherwise you either burn your hair, or not get it as straight as you want it.
Honestly, I prefer to press my hair the old fashioned way (I use two pressing combs with the oven) and use a good electric flat iron if I want my hair flat. I only use my marcels when I want to bump the ends a little...I love my marcel curling irons, though.
Let me know if you need any pressing/flat ironing tips. I'm a pro
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