careful + of + noun
Be careful of that man.

careful + with + noun
Be careful with the knife.

careful + about + noun
Be careful about the things you say.

careful + about + noun clause
Be careful about what you eat.

careful + about + -ing form
Be careful about discussing that issue.

careful + to + base form
Be careful to look both ways when you cross the road.

careful + not + to + base form
Be careful not to disturb your father.