Whenever you want but best time is 27-33 weeks
I had mine at week 35 (didn't think I was gonna have one, it was a surprise). But you may want to do it a Lil earlier to know what you did and didn't get for the baby and it'll give you time to get what you didn't get.
6-7 months prego so you have time to get what you didn't and get everything settled in its place. don't wait too long.
I'm be 33 weeks & 5 days when I have my baby shower .
I'm 31 weeks & 4 days now .