How can I prevent incisions scars when I go for a round 2? (photo)

The revision implies that there is less fat than the first time, and scar tissue will make the surgery much more difficult on the surgeon.  The percentage of fat survival in the BBL the second time should be about the same.  You will have to find a surgeon who does mainly revisions and is capable of getting fat where others have not been able to do so. Liposuction scars are about 5 mm or less.  Also, you should consider the number of scars made for an area.  One surgeon may use 3 for liposuction of the abdomen, sides, and back and another may use 15.The scars from liposuction will continue to fade in most cases for at least one year.  I advise that scars not be exposed to sunlight for the first year due to risk for hyperpigmentation.  If the scars are elevated or irritated or there is exuberant scar tissue, injections of several items may be helpful.  Scar revision surgery can lessen the scar.  Other alternatives such as Intensed Pulsed Light (IPL) lasers (Fractora, Lumecca) may be beneficial. Laser may be reasonable after the initial phase of scar healing is complete at the 6 week mark in an uncomplicated case.  However, I usually recommend waiting longer, because time will usually be the best help, particularly in a good scar former.

Dear MissDrea,
scar prevention begins in the OR during the surgery when I meticulously close wounds in multiple layers in order to reduce tension and reduce scars width. I tape my incisions during the early postoperative period to reduce micromotions of the tissues so the incision can heal earlier. I also use compression garments and later Biocorneum gel.
Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

It is essentially impossible to avoid incisional scars for any surgery. Much of how scars heal depends upon the genetics of the patient. Notably, darker skin persons typically form darker scars. On the other hand, you do not seem to have much fat and seem to be naturally lean thus making you a poor candidate in general for BBL.  Instead of considering round 2 BBL, you may want to consider something more reliable and permanent such as buttock implants. Glad to be of help.