My previous T was always asking me to not prepare anything and even not think about the sessions outside the office - so every single time I was prepared for the whole 50 min If I hadn't been, we would have sat in the silence as he has never asked any question and wasn't talking much...
My current T said that I can prepare topics for each session if it helps me so somehow I do not prepare much , rather like "oh, probably I'll talk today about this and that" but nothing detailed...