I'd like to reframe this, I think there's only one way to know if someone is a good fit for you - to have a proper, real, deep coaching session. As a software founder I have the idea of a "trial" baked into me, so I think this is no different here. I sometimes coach people for weeks at a time (there's no payment), so that both of us know whether this is right for us (I have the privilege that money is not an issue for me). So that I think is the most powerful, because at that point someone can truthfully commit and go all in and I think for a coaching partnership to be successful, that's the only way in my mind. When someone asks me I often say "let's coach and you can make up your mind after...", this really takes the pressure off, which can otherwise dilute a process that I think is honestly, holy in my book. In other words, if there's a coach you think could be helpful, ask them for a free, full-on coaching session so you can understand if there's a good fit.

And the most effective means to tune in in my experience are simply finding ways to slow down. Pausing, in talking, in walking, being in places that are less crowded. Tuning in during a walk in a park is much easier than in a busy restaurant. And pointing things out that you notice if someone is really charged about something, although that is a delicate process of course. But that's where I'd start.