What is some advice for a newly promoted E-5?

Remember your company's SOP's and be technically and tactically proficient. Know the jobs of those above you and be able to train every job of those below you.

Take care of your soldiers like they are your family. Train, discipline, and be fair to them. Treat them as people first, respect them as humans. Inspect what you expect, teach what you expect, pass on all your knowledge and make them better than you.
Do that and they'll follow you through hell covered in gasoline. After that, everything else is easy.

Don't forget where you came from and don't take crap from the ones that used to be your peers. They need to understand that you lead now. But don't be a dick about it.

First and foremost, congrats and welcome to the NCO ranks. I tell my soldiers they no longer have buddies and friends as E-4's and below. You need to segregate yourself from those ranks and become their leader & mentor. Find yourself a high speed NCO (peer) and a senior NCO that you look up to and ask them to be your mentor. Get to know the different Army regulations (AR 670-1 is one of most popular). Know how to lead PRT/PT at your unit (HUGE). Assert yourself into conversations within your peer group on many different things and be the NCO your leadership will look to for advice on a wide variety of topics. Be proficient within your MOS - make sure you know your job and what your troops' jobs are. Ask about leadership schools and when can your troops go (get them scheduled first and then look after your career). Get proficient at giving counseling statements (both positive and negative) along with how to fill our your own NCOER support form. Lastly, ask for a quick meeting with your 1SG (through your chain of command) and seek our their philosophy on leadership. Best of luck to you.

First off congrats and welcome!

The biggest thing I did (which I feel like helped ha) was remembered everything that my prior good and bad NCOs did to me.

I would try to expand on what what the good ones did that I noticed as a joe.

And most importantly think of any bad ways you were treat, bad ways that prior NCOs handled situations etc and do the opposite of that.

I felt like I was pretty much shit on (pardon my french) my first unit from extremely horrible NCOs and knew I would never treat my soldiers like that.

Then small things that a great mentor told me.. put you soldiers birthdays and big events in a calendar so you can always honor those days and such. Even if you cant cut them for the day, a simple happy birthday first thing in the morning shows you care about them and their details which builds that trust up immensely.

Congrats!

Learn where to find any thing a soldier asks. You may not know the exact reg off the top of your head but you should know the area in the books to find the answer and if asked ALWAYS find the answer for them.

1) When they come to you with a question, don't be afraid to say "I don't know". One of the worst (IMO) things that you can do is spout off with something that sounds official, but turns out to be not an actual regulation, or completely against policy. Research their question, then give them the answer. That way, you will also learn.
2) The E4s and below who were your drinking buddies yesterday are no longer your friends today. You now have a professional obligation to them, whether that means guiding their careers, or disciplining them.
3) Keep a copy of every counseling statement/award/NCOER that you write. Soldiers mess up, and they tend to do it the same way, time after time, Soldier after Soldier. It will save you time if all you have to to is plug and play names and dates for common infractions. Similarly, there are only so many ways to do a job, and it is easier to tweak an existing bullet comment than to make up a whole new one.