It may be a little bit confussing, but there’re some topics you can follow until you get used to the sharing feature:
Project Sharing | How do I share my project on IS/APP?
DIY Project Sharing Guidelines
Project Sharing |📸How do I create a quality photo of my project?
You can also navigate old sharings to see how others made them xdd
Even after you’ve already shared, you can still edit both the IS entry and the automatic topic generated here in the community forum. You can add the results pic to the opening description as first pic which is going to be the thumbnail.
If you still have any doubt, please don’t hesitate asking here, there will be many members willing to help 