Paint the ends of the log with any paint when it hits the ground, prefer a couple coats. It will start checking from ends.
I would cut at least 7/8 if you want to get 5/8", even better a full 1" , there will be humps, bumps and crooks.
Stack with sticks between and keep out of sun and wind, but in open shed.
Mill em as soon as paint dries good on ends.
That is what my dry guy says, yer mileage may vary! :D