What advice would you offer someone transitioning from being an NCO to an Officer?

Here's a few things I would offer:

Your time as an NCO provides you tactical knowledge and perspective. It will help you hit the ground running as a new PL. However understand that many of your duties will still be new to you. To use a personal example, there's a significant difference in maneuvering a fire team and fighting a Platoon. Leverage your experience and knowledge and learn your new duties as a Commissioned Officer. As a PL my PSG only had 3 more years time in service than I did. However there were still many times where he helped and guided me along the way. Your PSG is responsible for your development, make sure you listen.

Be prepared to be treated like every other green 2LT. Right or wrong, Soldiers are going to look at your rank and make assumptions before they know you. I remember a prior service SFC at BOLC who was furious when a SSG Cadre member blew him off when he tried offering advice. Even now with close to 9 years time in service I'll get slick-sleeve SPC's who automatically assume I'm an idiot simply because I have a bar on my chest.

Be prepared to dedicate a lot more of your personal time preparing for Battle Assemblies and Annual Training. You should be on step 8 of the TLPs when you have opening formation. To give you some perspective, as a Company Commander I spend close to 20 hours a week preparing.

Best of luck in your future endeavors. Commissioning is both a heavy commitment and an awesome job at the same time.

Remember that your new job is different. You have an advantage because you already know some about the Army.

Now, as said above, listen, learn, and lead.

The best advice I can offer is something that was told to me before I became a NCO. Don't forget where you came from. I've always admired those officers who were prior enlisted. They have an understanding of how the enlisted ranks operate and what makes them tick. If anything, being prior enlisted helps in relating to the troops better. Congratulations on the commission.