Helen congratulations!!! That is amazing!!! And, omg I know what you mean. Everytime I learn something new and go to share that I feel a tinge of imposter syndrome/ "am I being weird?"
Here's the answer that you might not want to hear but I promise is the fastest way. You just start saying it.
If you have some friends near ya ask them to ask you normal questions like "how was your day? Where do you live? what's your favorite movie? waht do you do?" the first few questions get you easily answering questions that normally come up. Then it is easier to just answer what you do. Then, you take that ease and you just channel it when it comes to be in a conversation and say "I totally understand, yesterday I was teaching a client Pilates and -__-happened." If people are intrigued they will ask more. If they are not they won't. Its not personal. xx~LL