The seed pods on my Mom's amaryllis started to fade from their healthy green color and get a little browm on the edges. I'd read you didn't want to seeds to dry out, so I decided to go ahead and harvest them now.
The pods were in 3 sections with papery thin seeds packed inside.
If the seeds are viable there will be a little lump in them - you can feel it if you hold the seed between your finger and thumb. I saved the viable seeds and discarded the rest. I placed them on a plate with wet paper towels on top and bottom.
I keep the paper moist and hopefully these little seeds will sprout in about 3-4 weeks.