I just permed my hair,then straighten it, but when I straightened it my hair always curls at the end

What is the best way to straighten my hair so it will go as straight as it can. And what should I use?

I just permed my hair,then straighten it, but when I straightened it my hair always curls at the end.?

Get a frizz ease or straighten serum from your local beauty supply store or even wal-mart, rub it on your ends, and then flat iron.