I think what they were talking about is - ironing your fabric to freezer paper to feed through your printer. The fabric should be treated so it doesn't fade as much, or at all. I just buy the pretreated fabric that is already to go through the printer.
Then I use my PrintShop program, design my label and then print it out.
Any time you feed fabric through your printer it needs to be backed with something that is stiffer. Starch won't do it. You also should make sure that there are no stray threads hanging off the sides of the freezer paper. You don't want them getting caught up in the printer.