I use the "perfect stems" method by Karen Buckley.
https://www.amazon.com/Karen-Kay-Buc.../dp/B077ZM6Z1W for the product and
https://www.youtube.com/watch?v=KnCS5pV85Hs for a tutorial.
But you don't have to spring for her expensive heat resistant plastic thingys. They are simply heat resistant wire ties that you can get in assorted widths for making the bias tubes. You can pick them up at any auto supply store like NAPA or Advance Auto, I suspect Harbor Freight has them too.
Yoko Saito also does beautiful delicate stems. Here is a youtube video of her tutorial.
https://www.youtube.com/watch?v=faJ2K4Ynsiw