If I am going to have my neighbor look at/fix my computer, what do I need to do so he can't view the internet sites I go on?

I have been having connection problems with my laptop. I am not tech savvy at all, so I am going to have a neighbor look at it and diagnose what’s wrong with it.

He may do it in my house, and if he needs to, he is welcome to take the computer home to look at it.

What do I need to do so he cannot see the sites I have viewed, and so Google does not show him what I have googled?

He has lived in my complex for about 10 years, and he’s well known by my neighbors. However, because I am not around too much, I don’t know him too well and I don’t want him to have access to my innermost secrets!