Here is posting using Tampons --I prefer this method as its fast, and if you use painters tape, (instead of sport tape) it breathes and easily tears off when changing the posts. I do not like having scissors around their ears, I have heard so many horror stories of "oops the scissors slipped" so if you use painters tape you can gently tear it off.
Start with a tampon that is the length of the puppies ear, here is pictures of a tampon, and 2 types of backer rods, one bigger, one smaller, already stiffened with Gorilla/Duct tape
Take the tampon, and tape the top to the bottom to length; pulling some fluff out-the bottom; the fluff protects ear canal and absorbs moisture.
Backward wrap painters tape on the tampon, (or Backer rod) and insert in ear, fluff side down. If using Backer rod, insert with a side down that you cut half off, so it rests gently in ear canal.
Have strips of tape ready, and stick the tampon in the ear and wrap top, then bottom, do other ear, then add more tape all around. I don't use a bunch of tape until the tampon is set right, so I can adjust it if necessary.