What is the best way to come out of training with the biggest headstart to promotion besides using what I've been taught

Hello Leighton, thank you for your question.
I can only offer my opinion on this as everyone will experience different paths towards promotion but I can tell you how I was promoted?
I am a HR Specialist in the Adjutant General's Corps and our promotion is fairly quick compared to other roles in the British Army. I've found that the best way to be promoted was to have a positive attitude towards everything. I wasn't afraid to put myself forward for courses and exercises even if they seemed challenging and daunting. I also kept my fitness level high and I also volunteered with charity work in my own time. You will have an annual report written on you and if you can participate in extra activities outside of your normal role then your boss will have lots more to write on you.
My main advice? Stay positive, work hard and be a team player.
This will differ depending on what trade you choose but that's my personal experience in the Adjutant General's Corps.
Good luck in your career.
Zoe