Wondering if other successful people have ever encountered this and are part of this sub.

I run a good business and do well, increasing by a good amount year over year. This year is the first time I'll be presenting knowledge from my field to larger groups (ie 40-100 people at a time). I've finally reached the point where I'm not only doing, I can teach others to do as well.

Problem being I have sabotaged myself in the past by having impostor syndrome (stems from childhood issues) - thinking that I'll be exposed as a fraud when I lecture or teach even though I am an expert at what I do. Has anyone here ever encountered this and have a good way to deal with it or resources?

There's the whole "fake it till you make it" idea, and in the moment I can do that, but the preparation and self promotion part is always an issue for me.