How to not accidentally insult people? (srs)

I always seem to do this stupid stuff where I say something meaning something a bit playful or joking and a girl will take it is an insult...like I joked a girl about her liking food tech as a bit of a sexist joke and she thought i was insulting her weight...seriously I do this so often. How do you guys watch your mouth around girls to not offend them?

Put the internet to work for you. via Personal Recipe 2629979