Bogging to a stock pile
When loading a stock pile (S/P) always push the dirt up into the S/P and load left to right.
Loading a Truck
If you are loading trucks and bogging headings at the same time hopefully the engineers have placed a S/P near the loading bay as time management and full buckets are important. This makes life easier because if you load two full buckets on the back of the truck and get a half bucket from the S/P this is normally enough to fill the truck allowing you to load the S/P in between trucks.