Hi Sasha. It’s never really going to sound natural because the piece you’ve taken is literary prose, so more poetic and illustrative than any person would use day-to-day. I haven’t read the book, so I’m just going off the paragraph you have copied here. The writer is portraying the disgust he felt when he saw the Martian. “Clumsy deliberation” highlights the strangeness - even though the movements are deliberate (which would normally imply careful and steady movements), they are clumsy. The use of “tedious” - to me, it means the movements are slow and boring to watch. My advice would be not to spend too much time trying to understand each little bit of the sentence. Let the words come together to paint a picture. I hope this helps!