PLS help. New chin soon!!!!

Hi! So I decided my chin is lonely and I am gets her a friend soon. First, I don't really know how to introduce 2 chins? I have a ferret nation cage and also a backup smaller cage I can use for the new chin. I understand that they may not like each other and the owner said if it doesn't work out she can take her back.

Please inform me on how to introduce 2 chins. :)

Thanks!