Martha, I see you did not get a good answer to your question. You can copy the URL of the g2g post and paste it into an email message and send it to the non-member.
The URL is the web address in the box at the top of your web browser. It typically starts with "http...". For example, the URL of this particular thread is :
https://www.wikitree.com/g2g/611825/how-do-i-forward-this-answer-to-someone-who-is-not-a-member-of-w?show=611865#c611865