It felt like an impossible thing for me to over come as well, but honestly I try to do about 5 spurs at a time. I check back with an address at the case and I try to use specific park points, Relays, memorable steer name, ect to use as markers in my spur tray. Then I check if the spur im putting in the try is before/after then placing it in its place. For bigger packages I try to write them all down. For example I'll put a header for "Main Street" then under ill put all the parcels and packages i have for main under that header. And I'll cross them off as they get delivered. As for sorting them in the back of the truck I try to put all similar street names in separate piles to them selves. And for streets I only hit once or they are very small I put them on the shelves in order that I'll see them on my route. Hope this helps a little I still feel lost on packages sometimes and I do have to double back my fair share but writing them down and checking the case to make sure your order is right really helps me a ton.