First and foremost, always follow the manufacturer's guidelines when caring for your red sweater. Otherwise, there's more you can do to ensure your red sweater never fades. It's actually best to handwash your sweaters, but I understand that not everyone will do that (I do but that's just me). First, wash reds with reds, only wash your clothes on a normal cycle, and turn your sweater inside out when washing. Avoid putting the sweater in the dryer if you can. You can also wash your sweater with salt or baking soda to ensure your red sweater stays vivid.