One of the things that I find myself doing regularly is stepping back before providing all the answers. As a Manager, what I say carries weight, whether I want it to or not. When a Supervisor comes to me for advice, I have to be careful to "ask" what they want to do as opposed to "telling" them what I would do. It's two-fold, this approach.
One, it allows your Supervisors to be responsible for the decision they are making. If I make the decision and the staff member gets angry or is unresponsive to my approach, the Supervisor can beg off by saying "Juin, told me to do this" which is a bad learning experience for your Supervisor. If your Supervisors do this, they give away their power and honestly, I don't need them to constantly defer to me (otherwise, why do I need them). If a Supervisor doesn't come in with an idea of how they want to handle something, it also makes it easier to stop the process when it doesn't go as planned.
Two, if the Supervisor makes the plan, they are more inclined to make sure it goes off without too many hitches. They have buy-in because it's their plan. And it allows for growth. And you show your staff you trust them.
So the next time, you are asked for your opinion on something, instead of answering first, ask what they think first. They have the answer inside themselves already. You don't want to second-guess yourself by always feeling like you have to know all the answers. And as your team grows by knowing you trust them to come up with great answers themselves, you grow by letting them be the Supervisors you hired.