Over 6 months post lip lift - What can I do to minimize scarring? (photos)

At least from the photos provided, there appears to be a hypertrophic (elevated) scar in the very center. This can usually be easily flattened with an intralesional injection of an anti-inflammatory agent, such as triamcinolone in the appropriate concentration and amount. I have found silicone gels, sheeting, etc. to be generally ineffective and have not recommended these approaches for many years already. You would be wise to consult with a board certified cosmetic dermatologist. Going forward it would be well to keep in mind that the ideal window of time for treating any young scar is between week eight and week twelve following surgery (or whatever the cause) since treating a "mature scar" (older than three months) is much more difficult and is likely to be less successful in general. It is for this reason that it is not preferable to wait six months or a year before treating. Once the scar is flattened, if it remains hypopigmented, professionally performed microneedling accompanied by the application of prescription pigment promoting topicals, such as tyrosine and lanatoprost, may be used to improve the pigmentation and to better blend the color and texture of the treated scar with that of the surrounding skin. Hope this helps and best of luck.

At this stage you can still hope that scar will improve; it takes 12-15 months in your age group for scar to completely mature. Injection of Kenalog or laser treatment should be considered as well. Good luck.