Read their stuff. It might be things on their website or their book, just get the relevant information yourself first. Be kind. If possible, provide them with some useful information first. They have no obligation to answer you, so being kind will lead them to want to answer your questions one.
How to Email People Cold and Get A Reply
How to Email People Cold and Get A Reply
How to Email People Cold and Get A Reply
Read their stuff. It might be things on their website or their book, just get the relevant information yourself first. Be kind. If possible, provide them with some useful information first. They have no obligation to answer you, so being kind will lead them to want to answer your questions one.