Set clear boundaries
As INC.com points out, wanting to maintain an open and friendly relationship with subordinates does not mean there should be no boundaries in that relationship. Clearly communicate to your team what you expect from them and what the limits are. Within those limits, aim to foster the warmest possible rapport with your team.
Don't be controlled by emotions
Be consistent in your expectations and values. Always act fairly and avoid letting emotions influence your decisions or interactions with subordinates. Only then can you build a strong and open relationship with your team.
Be as authentic as possible
Don't pretend to be someone you are not. Avoid being too authoritarian, but at the same don't try to be a poor comedian or excessively friendly. Find a managerial style that suits you and stay true to it.
Give subordinates space to work independently
Don't become a micromanager, but don't neglect supervision either. A well-balanced approach is to allow team members space to work independently, while gradually shifting some responsibility onto them.
Delegate work effectively
You can avoid potential misunderstandings by delegating tasks clearly and efficiently. Communicate your expectations unambiguously and explain the context so that subordinates can work on the task as independently as possible.
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