I myself have gone almost a whole year without a missload. Last time I had one was a few weeks ago, and that was an add/cut not pulled, for obvious reasons I wont explain.
One, check twice.. Check the ink stamp twice, once its in your hand and again while entering the car. Two, make sure your in the right car and placing the right package on the right shelf or floor space. Three, learn to write and walk at the same time. Four, learn the area you are in.. this is simple, memorize what your cars look like on the inside. Is it dark inside? Or is it lighted well. Is there a grate to walk over first and / or is there a step up into a car. Recall car lengths and load styles within. Had a preloader put two missloads in my car a few months ago, I recalled the area within and found both without even trying.
Its too hard to missload really. But you cant really be fired for them. They will claim its " missloads " but falls under production article 36. All hubs try their tricks around missloads. Either it be prizes each week or month without them, to getting writ up for just having one. Just recall that you are human and we do make mistakes. Just try to take some of my examples or suggestions to hand. You will be a master in no time.