How to Make a Terminator Costume. Many children of the 80s remember a time when Arnold Schwarzenegger was not a governor, but royalty among action superstars. In 1984, he cemented this title when he starred in the Terminator. As imitation is the most sincere form of flattery, there may be some of you who'd like to dress as the villainous cyborg for Halloween. Here are some tips for how to make a Terminator costume.