Article continues below advertisementMartha Stewart is proving once again she's still got it at 84 years old! The TV icon lit up Instagram with a fresh mirror selfie, puckering her lips for the camera and showing off her glowing complexion and sultry side.Article continues below advertisementIn her caption, the lifestyle queen gave credit to her go-to skincare product."Despite the finger smudges on the @elmbiosciences serum bottle cover-we will be more careful in future - this selfie shows how beautifully my skin has responded to every day applications of A30 serum. My skin is tight.