What helped you as a newly appointed PSG? Things you wish you would have known sooner? Any advice or tips?

SGT (Join to see) My first advice is always, "Do the best you can with what you know now; until you know better, then do better.

Then the usual suspects:
1. Own your Platoon, its achievements and its shortcomings. Know the measures of success (according to the CDR) and work to improve them. Celebrate the wins with your Soldiers. Take the blame for its shortcomings by understanding where you could have better prepared yourself or your leaders. Failure in training is an opportunity for growth, make this culture acceptable.
2. Empower your junior leaders. Just like the CDR should support disciplined initiative and lead through intent, so should you. Unless a task is steeped in doctrine, let the junior leaders figure the "how to get it done".
3. In the same vein, don't put your leaders in a position to fail without you. Brief, Train, Rehearse, execute. While you assess and provide feedback every step of the way.
4. The PSG is the PLT's master trainer for all tasks (warrior and MOS), skill levels 1- 4. If you are not an SME, get there. If your junior leaders are not SME (in SL 1-3) get them there.
5. If training your PLT to execute their mission is Job #1, taking care of your Soldiers is Job #1a. Understand "taking care of Soldiers" means YOU: get them fed, get them the equipment they are supposed to have, get them paid, get them leave, get them recognition, get them promoted, hold them to account for wins and shortcomings.

6. Never stop developing yourself. Read. Find out the BDE CDR's reading list. read leadership books. Your leadership style is still evolving, but inundating yourself with information will give you options and provoke thought and conversation with yourself, your peers, and your rater / senior rater / mentors.
7. take classes. Take a look at the Army Leadership Requirements Model. Build capability in communication, conflict resolution, change management.
8. Build your network. Establish positive relationships with the company and Battalion Staff, other Platoon Sergeants, CMF SMEs, base POCs. These are resources that can provide mutual aid in a pinch and generally make your life a little easier for routine BS and a connected Army is an Army that moves more efficiently.

9. Be visible. Soldiers need to an example to follow, in the absence of a good one, they will follow their favorite, and sometimes that isn't you. Make it easy for them to communicate with you and your junior leadership. If you are not accessible, you won't know about issues until they become operational corrosives.
10. Adopt a zero-tolerance policy for anything that is a detriment to the health, welfare, and safety of your Soldiers. You are the shield to their wellbeing. You must be resilient. But there is also "acceptable risk". Ensure you understand the CDR's risk assumption authority and how to mitigate as much as possible.

Whatever CSM Everroad said I believe is totally right

1) Value the leadership concept of delegation. As a squad leader you were in charge of x-people. Technically you're in charge of more now, but you should have less people now who answer directly to you.

2) Trust your squad leaders and provide them guidance, but also don't be afraid to tell them you don't have an answer if you don't. Same goes for anyone in said squads. Subordinates can smell when you're lying before you finished said lie.

3) Follow up with your squad leaders and any under them who have issues that stand out. You don't have to necessarily ask for details that aren't relevant, but inquiring on the general status of any issues can show that you do care (which I'm sure you already do).

4) Kind of with #2 always tell the truth no matter how politically incorrect it is. Six different units in, and I've received far more respect than disrespect for doing this.

5) Get superiors involved only as needed. As the SpecOps saying goes: if you can minimize the threat you do so. If you can't minimize the threat you call in someone/something that can.

6) Don't forget your role as a Sergeant of Soldiers, and that you were given a billet with which you can serve them even better than as a squad leader.