Producing my own feminized seeds - Colloidal silver or Tiresias?

[Curly Beaver]

I will have a plant in flower in another week and would like to try to self pollinate her. I havel mostly read about colloidal silver but also Tiresias occasionally pops up.
Is there one "BEST" tutorial on making seeds, and if colloidal silver is the way to go, which product (ppm.)
Thanks in advance