I have Aetna. Before being banned I had to go to a doctor for 6 months ( Seeing him once per month) and go on a diet. I also had to do a dietitian consult and psychiatric consult ( Which i did in the 5th month) . I would first choose who you are going to have perform the surgery and go to them for the 6 ( or however many) monthly visits. From what they told me, they have a special form to fill out and keep to send in the the insurance company and most doctors office ( like a primary doc ) doesn't document the things they should and one mess up could ruin the whole thing. They have to write down weight , new eating habits , and a few other things. There isn't a way to fast track it... I wish there was!! My time actually went fast. My one biggest advice would be to really work on the pre op diet. I didn't lose any weight in those 6 months. It would have made the big changes to come much easier if i would have worked on new habits then rather than going "cold turkey" LOL I was also approved on the first try. It did take about 2 weeks however!
Best of luck!