Guidelines for markings before mastopexy

Note: I am not a fluent english speaker, pls excuse my mistakes. Hello, I am a mother of 2, 32 years old, I had breastfed for 4 years, and after weaning, my breast are very deflated and saggy. When I lay down my skin gathers awfull. I am from S Europe, and my only option, please don't ask my why,  for mastopexy is a doctor from my town, which is a brilliant doctor, well knowed for his results in plastic surgery, but with a smaller experience in breast surgery. I trust him because I've seen reconstructed hands, legs and faces, and the results and the scars are amazing. I've only saw a mastopexy made by him 20 years ago, and I couldn't believe how beautifull it was. So, I trust him as very good surgeon, but I need to be sure the markings before surgery are made correct. Could you help me with a few guidelines, on how the markings on t shaped mastopexy without implants are made? And another one: he told me he will make me an internal bra. Is the internal bra suited for my breasts? Thank you in advance for your answers!