What's the best way to prepare your body for lipo the year before? I want lipo of the waist /abdomen/ flanks.

It's a good question. The best way to prepare is to reach your goal weight prior to surgery. This gives you the best opportunity of having long-lasting results. Eating a well-balanced diet will help you recover from surgery. Find the right surgeon! Do your homework and have consultations with board-certified plastic surgeons.

Honestly, liposuction can help achieve something that diet and exercise cannot.Kenneth Hughes, MDLos Angeles, CA

Being at your ideal weight is key.  Make sure you are off all aspirin and aspirin containing products, diet pills, and herbal supplement.

I recommend getting a formal evaluation with a body sculpting expert for recommendations. It is recommended to be at or near your ideal weight. For best results, I recommend a hi definition procedure like VASER liposuction. I use VASER HI DEF with ThermRF and fat grafting to get the most fat removal, skin tightening, contour and definition. This combination will give you the most toned result. I recommend getting a formal evaluation with a hi definition physique expert. Best, Dr. Emer

If you are healthy and live a healthy life style then there is really no preparation required at all for cosmetic surgery.  That said, you should be not be taking any supplements or any medication that can thin your blood like Motrin, Aleve or Aspirin.   Many surgeons will give patients a very long list of "not too's" like do not drink and do not take supplements of any kind, but that is to cover all the bases since some patients do not think that is relevant.  What I simply say, is do not take anything the week prior to surgery.
As far as exercises and weight, there is, again nothing to do if you are at your ideal body weight.  If you work out regularly, keep going.  
The one recommendation for any cosmetic surgery is to be at your ideal weight.  Usually this means that if you are carrying some extra pounds, your results will be better if you can shed them before your surgery.
I hope that helps.
Best regards.