How do I become a diplomat ?

I’m a 21 year old female with no college degrees at the moment. I’m leaving for the Army with a job as ‘Human Intelligence Collector’ which is in the field of language and interrogation. I’m wondering what are the steps to become a diplomat, and how do you know when you are one? Does military training help a little bit? My plan is to go into the Army and go to school while in. I’m not sure what I should even begin to study, but I know I want to become one. Thanks

The area I like is Human Rights and Diplomacy. I also like Photojournalism but that’s a hobby.

I’ve never met a diplomat or anyone in that field so I didn’t know where to ask.