Just finished Witcher 3 and got the bad ending. Properly traumatized.
Edit: As far as I can understand, the 3 places I went wrong were: Telling Ciri she doesn’t have to be good at everything, joining as backup with the mage meeting, and not trashing the lab (I thought the necklace scene was sweet).
Consider yourself lucky, I got the good ending and had no reasons to start playing again from the beginning…
I don’t have a ton of free time so I think I’m just going to have to be satisfied watching the endings on YouTube.