Hello and welcome. You have posted this in a forum dedicated to articles for a future front page for the site. You might find it worthwhile to ask a moderator to move it to the Poly Relationships Corner
instead as people are more likely to see it there.
People post here with similar questions fairly regularly, so you can use the search function to find their threads for general information. Given that you say you've decided to open your marriage by "meeting a girl" who I presume you mean to share, you may also benefit from doing a search for "Unicorn hunting" as there are some well-known pitfalls along that route.
In answer to your question, though, yes, you can get it right if you put the work in.