They're pretty confusing to me too, I'll admit.

But firstly, don't do it when I tell you. Just do it because you want to make things better. If you don't, don't do it.

And when you do it, instead of looking for little things to compliment him on, acknowledge that you want to apologise for what you did before, and try and have a civil conversation with him. Without... making comments on his humanity or anything. Talk about science, and things you might have in common. Treat him like a human being, and an intelligent one, and he might see that you mean it.