In casual speech, putting "all" in front of an adjective can make it sound more negative. Use it to talk about things that you don't like or that annoy you. For example:

Don't get all impatient.

She likes to act all shy when you first meet her, but within ten minutes she'll be talking your ear off.

He gave me his old computer, but it's all old and crappy.

You can even make positive descriptions sound negative using "all":

Why are you being all nice to me today? Do you want something from me?