Well, I've been shown two different ways to do this. The first way I was shown was to cut your cs (SU! is what I've always used) to your desired size, then ball it up continuously until the cs starts to separate. The, gently pull it apart. This will give the crinkled look to it.
The second way is to cut your cs to desire size, then start to rub your bone folder on it like you curl curly ribbon. It will begin to separate, then you pull it apart gently. This gives you a smooth appearance.
HTH!!