So me and my primary gf (Lisa) are poly but for now its just the two of us.

(Keep in mind Lisa knows about everything and is consenting)

Now I've found a girl (Anna) who i am interested in dating but im fairly certain she never even heard about polyamorie.

I might go on a date with her (Anna) on Saturday, but im not really sure how to go about this.

Its the first time dating someone else while in a relationship with (Lisa) the fact that (Anna) probably never even heard about it.

Do I tell her (Anna) straight away (on the first date) or do we first see if there is a connection and tell her then? (Second or third date)

Any other tips are very welcome too!