How to mow a field to have less grass to mow?

I have a zero-turn and have to mow a field with long grass. So I don't have to rake up grass from all over the field, which way should I mow the field? Start on inside and work my way to the outside? Or, start on the outside working my way to the middle, in hopes of getting a pile of grass in the middle, only. Or, would I mow back and forth?