Make sure you are responsible for your actions.

Meaning: This means that you should take steps to ensure that you are taking responsibility for the things that you do. It means that you have to be aware of the consequences of your actions and that you have to be willing to accept the blame if you do something wrong.

Choice of Words: Make sure means to take steps to ensure that something happens. You is a personal pronoun that refers to the person being spoken to. Are is a verb that means to exist. Responsible means to be in charge of something or to have to take care of it. Your is a possessive pronoun that refers to something that belongs to the person being spoken to. Actions are things that you do.