How Do You Lay Down After a BBL?

When performing a BBL procedure, I recommend to my patients to lay on their stomach for the first month while sleeping to keep pressure off of the gluteal area.  You cannot sit for the first 10 days post operatively for the same reason.  When you transfer fat from one area of the body to another, the fat needs the blood supply from the surrounding area to grow into it for it to survive.  Typically, you will keep 70-80% of the fat which is placed into the gluteal area.  If you sit or lay on your buttocks you will be compressing the area and in addition to all the swelling which is there post-operatively, there will be a decreased amount of fat which will survive.  This is also the reason why I do not combine tummy tucks and breast procedures with BBL's as you need to lay on your back post-op for these.  To get the best result you need to follow a specific post-op instruction to allow the fat to survive.

Hello dear!!
Thanks for the question and provided information as well. 
You can adopt the position that best suits you and in which you feel most comfortable, preferably on your stomach. It helps to use several pillows to accommodate yourself. 
If you have any concerns, please follow up close with your plastic surgeon.
Good luck :)