Usually if someone asks me to do something or if they can do something, I say 'I don't care, sure'. I don't really have strong preferences. What movie we go to, where we go to eat, I couldn't care less.
There are some things I care about, and if I care about it usually I'll express that preference and people will let me have my way with it. I've been called stubborn before though, so usually I'll get my way even if it's disagreed upon. But since that so rarely happens, most people see me as agreeable.