How can I make my Facebook more private?

[cupofteaplease]

I have changed my settings so that only friends can see my wall and photos etc.

However, today my MIL commented twice that she had seen comments I had made on other people's wall posts or status updates. To be clear, she is not friends with these people. I don't really like the thought of anyone being able to see things I have written to people they don't even know! This is not about my MIL, by the way, I would feel the same about anyone else too!

Is there a setting I can apply to stop this happening?

I think it is due to the fact that the friend whose wall you are writing on doesn't have privacy settings in place - so anyone can see their profile. The fact that you're friends with this person means that when you write on their wall, it could come up in your friends news feeds that you have done so and it will be on your wall that you have commented on someone else's wall and then your friends can view their profile (if they don't have privacy settings.) Hope that makes sense!
I haven't yet found a way to stop this happening (I don't like it either) other than try to encourage your friends to put privacy settings in place.
I hope someone has a better answer than that, because I would like to know too, but I really don't think there is.