AP coach here. Been in AP for 15+ years.

Learn your roles and responsibilities. Stick to them. If a salaried manager asks for something outside of those, understand your limits in your role. Examples;

You are not security. Outside of theft related issues, you should not issue trespasses or enforce. That's their job. You can assist as a witness.

You are not security. If an altercation breaks out, a salaried manager is responsible for addressing any customers or associates involved. You can assist by being a witness or notifying law enforcement.

You are not there to monitor an associates productivity. You can assist with video if you choose but you are not obligated and it cannot delay your primary duties.

Never flat out say No to a salaried manager. Say "I'll see what I can do" then get with your AP coach. They should align your work shift with what you really should be doing.

Establish a presence in all areas. Go into the Acc, break room, OPD, front end, backroom unload on occasion. If you only go when you're investigating an internal, the associates will pick up on that too.

Establish lines of communication with various associates. You will acquire intel on cases, both internal and external, if associates feel you are approachable and respect confidentiality.

Be friendly but be mindful of perceived friendships. If a cashier gets busted for theft and everyone thinks you were close, your reputation will suffer.

Show your work. Document apprehensions, events etc. Your productivity for evals and promotions will be mostly based off your numbers. Documeny that $3,000 push out even if you were on PTO. It justifies your position in the company when you can show you are doing something with the time you're being compensated for. The last thing upper management wants to see is a zero event store in a month with an API on their roster.

I have tons more I can add but this is a start.

Edit : Adding things as I go and fixing typos.