How to C-Fold a menstrual cup. The C-Fold, also called the U-Fold, is the simplest and fastest way to fold your menstrual cup. It’s good for those who already have a grasp on inserting their cups and just want to get it over with, potentially one-handed. The drawback of the C-Fold is that it can come open at the rim while inserting if you aren’t careful, which is why we recommend the punchdown fold for those brand new to cups. You can find our full how-to folding guide on YouTube or on our websi