Baby registry!

When did you start planning your baby registry? This is my first time being a mom and I’m due March 12. I will be throwing my baby shower end of January. I’ve already booked where it will be (only because the church we are having it at, you have to book in advanced) and I just picked out the theme (my fiancé mother is planning it and she is always busy so she needed to know what theme and everyones address for invitation) so the only thing I need to do on my part is the baby registry and I’m just curious to see when any of you did yours?