I agree with the LST but I'd recommend doing it only to very strong growers. Autos that are not very strong growers will likely not benefit from any training because they will not grow fast enough to fill out properly before flowering kicks in. Maybe try taking one or two of your fastest growers to test it with?
Even though autos will not give you all the time you need to train perfectly, I'll share my method with photoperiods as it may help you to recognize certain situations and adjust your training if needed.
Tie down the main stem and let the side branches catch up in height and overall growth. As this is happening pay attention to the height of each branch...the plant recognizes the top closest to the light source as the main, so to evenly distribute the growth make any top that you want more growth out of the tallest and it will begin to fill out. And the tallest will stay above the rest until you lower it. This way you can achieve an evenly distributed canopy of even sized colas.
But remember this technique is great for photos because you don't have any limit on veg time...with the auto you might not want to switch up your "mains" too often as each time you do there is a slight lag period in which the plant readjusts it's growth pattern.
Sorry if that was confusing at all, but I really hope it does help in some way when the time comes!!