I never heard about this technique. The attached link is easy to follow with great photos. I'm going to give it a go.
https://growingfoodsavingseeds.blogspot.com/2016/06/gluing-chilli-flowers-way-to-save-pure.html
https://growingfoodsavingseeds.blogspot.com/2016/06/gluing-chilli-flowers-way-to-save-pure.html