Only employ people you:

a) trust b) respect c) know are better than you

...I can't stress how important C is. Always surround yourself with people who are better than you.

My best project managers are the ones who understand the process and the time things will take on average. If they know that it takes "x" amount of time to amend some assets, that really helps.

Second, positive re-enforcement cannot be underestimated - however having high standards (which you yourself reflect by being very organised, having detailed project plans and spreadsheets) is essential, as your designer will sense the standard they need to adhere to.

Third, understand that you are not the only busy person in the project chain. The ability to be the buffer between the client and your designer may at times be very difficult, and your designer thanks you for it, but if you can transmit a feeling of serenity at all times you will get a better working team out of it. This also has the added benefit that the one or two times that you are seen to be panicked, and you need things doing in a rush, your designer is more likely to respond positively to that need.

It's an art, and in about 10 years of this I've only ever had about 3 genuinely superb project managers.

I have one thing to say overall: Absolute transparency. This will help a lot in every situation.

One of the best things we do is to have a Project Manager to manage the projects of the other Project Managers. This redundancy ensures everything always gets a second set of eyes and input, as well as ensures that every project follows our methodology. It also helps resources (especially people) not collide or spread too thin. This person is like Air Traffic Control. It's a huge benefit.

I really like the articles from Julie Zhuo, the product design director at Facebook. She has some really thought-provoking articles on Medium.

https://medium.com/the-year-of-the-looking-glass

Hopefully some of them are helpful!

Fear-based Management

"Listen to them during lunch." They might be share some of their personal problem, once they close to you and you're slowly showing that you care. I believe that they will follow your lead without you actually lead them.

I would also like to know the answer to this. Piggybacking off of your question:

How are other companies/agencies structured? How often do critiques happen and how are they structured? How does mentoring work?

I've only been doing design for a little more than a year, and I'd love to know more about management/structure at other places.

Probably a difficult question to answer concisely. Could anyone recommend any good books on the subject?