So I bought the Emperor Edition, I really enjoy the design process of this game and hope to see more of the G2G system in future games. I would like to know how to link my forum account to my steam account(or any way to prove I have the Emperor Edition)? Is it the multiplayer code that pops up when I start the game or is it by email or some other method? I would love to know.

Good morning Bacatronic, and welcome!

This may be what you're looking for, from the FAQ thread /#/endless-space/forum/34-faq/thread/14953-endless-space-faq

"Question: How can I redeem my steam code in order to get the extra G2G points from my pre-order?

Answer: Login to the official site (not the forums!), click on your name in the upper right corner and type/paste your steam code in the "Redeem G2G Code" field, then click the "Redeem" button."

If you have Steam, when you launch the game it will display a key. You put that key into the Redeem G2G Code box on your profile.