+1 on MC Mustang's post.
To answer your question - I was Army Reserve also got Commission thru ROTC. I could offer you lot of advice but my fingers would be worn out, but here:
1. You much genuinely CARE for your soldiers; they can spot a fake a mile away.
2. Leadership is a 24/7 job, and somebody is watching ALL THE TIME. Keep your personal affairs in order also (money, women, drinking, etc.) If you can't, you lose their respect.
3. Soldiers like leaders willing to take personal risk on their behalf when it's deserving.
4. You must be willing to do anything you ask them to do, and every once in a while you have to prove it.
5. Sometimes, It's a lot easier to get forgiveness than permission.
6. Regulations are for the GUIDANCE of the COMMANER, and sometimes, you have to break them to do the right thing.
7. You can get away with almost anything as long as it's not about YOU.
8. Get/Stay in top physical condition - you don't have to beat the fastest guy on the run, but you'd damn well better be in the top third!
9. Go to as many schools (Airborne, Air Assault, Ranger, etc.) as you can - "street cred"
10. See out officers in your command that you respect; watch, listen, learn and let them mentor you - a good officer is always looking for someone junior to mentor.
11. You are NOT their buddy; you are their LEADER - and sometimes that means tough love.
12. Your PSG/1SG/Senior NCO can be your greatest resource - it's in his best interest for you to develop into a good officer, and all the good ones KNOW IT.
13. PERSISTENCE IS THE KEY TO EVERYTHING.
I retired last month after 25 years. It is hard to leave something I've done my entire adult life. Most of my friends and who I identify with are soldiers - and I wouldn't have it any other way. There are always bad eggs (they eventually screw up and usually get weeded out), but there are some true gems and those are the ones I always looked for.
Best of luck