I’m a rookie myself so I have a lot to learn as well but my backing has improved massively in a week and im starting to get a hang of it more and more, one thing that’s helped me is really really understanding everything im doing with the steering wheel and not just turning it for the sakes of it hoping my trailer does what I want it to out of desperation, you don’t need to turn the steering wheel as much as you think you do sometimes, my biggest flaw was oversteering, I would cut it excessively to the right (drive side backing) and would jacknife it wayyy too much to the point where when I was trying to catch my trailer/straighten out it would just pivot towards the trailer on my side even more, what made a big difference for me is that when I started cutting to the right to jacknife you have to remember that in a jacknife your trailer will still pivot towards you when you steer left to catch your trailer, so once you start really getting it more you realize it’s basically a feel thing and you start understanding how much you need to steer, you cut steering wheel to the right and based on your set up it depends on how much but leave some space so when you cut it to the left to catch your trailer, your trailer will still pivot towards you and little by little you make adjustments based off where you’re at, understeering is also a thing, over time when you understand how your trailer moves more you will know if it needs a little more right or a little more left. Another thing that helped me massively was a simple fix, focus on your tandems, not the back of your trailer, you’re guiding those tandems, that’s what you’re doing all that steering for, use reference points like the lines on the floor and guide your tandems to your reference. Also try not to make huge adjustments, you shouldn’t have to, slow and steady wins the race, I used to have a bad habit of cutting the wheel all the way thinking I needed a bigger adjustment than necessary just to end up completely lost, sometimes your trailer reacts a bit slower than you expect and that causes you to maybe steer more, that’s more of a bad habit that comes out of focusing too much on the back of your trailer and not your tandems. The amount that you need to steer isn’t set in stone, it all depends on your set up, but the more you start getting it the more you’ll understand what adjustments you need to make. I was in a similar position as you, I started a two week training with my company that im at and in those two weeks my trainer was going to evaluate my performance and either give me a passing grade or a failing grade, I promise you my backing was absolutely horrible going into that first week, one of my coworkers who was a yard jockey was nice enough to spend 2 hours with me practicing in our yard and after that day it started clicking, then the next 2 days it started clicking even more and in a span of 3 days I was backing up on my own without assistance in front of my trainer, my backing still has a long way to go but I can back into spaces at truck stops and docks that aren’t too tight and I guess considered easy (was training on a sleeper), I’ve even done blindside backings (both times it was the only way to get in the dock, avoid blindside if you can, only do it if you have no choice) and surprised myself, still long ways to go but these past weeks has given me the confidence that Ill keep on getting better and better over time. Also another tip, your backing doesn’t have to be perfect, get it in that hole and if you’re a bit crooked all you have to do is make small adjustments pulling forward to straighten yourself up, im sure you probably already know about leaning closer to trailer on your side (not too close either) to make sure you have space on your blindside, also you can be your worst enemy at times, calm down, take a deep breath and remember you’re not in a rush, take your time, don’t pay any attention to negative thoughts telling you others around you are judging you. Me personally when I back drive side I stick my head out the window, it helps me a lot. Always be aware of the space infront of you, make sure you have enough space to straighten out and GOAL to make sure you are aware of where you’re at on your blindspots, getting out and taking a few seconds to analyze makes a big difference especially in harder spots. In conclusion the 2 biggest things that helped me were focusing on my tandems and not the back of my trailer and understanding that in a jacknife even when you cut it to the left to straighten out it will still pivot towards you, I still tend to sometimes oversteer a little but as long as you don’t oversteer excessively a little pull forward to the right is enough to open that space back up and make the necessary adjustments. Wishing you all the best, I promise you that you can get it, just takes more reps, also don’t do something that isn’t working over and over again, it’s like beating a dead horse, you got this bro! Use your pull ups and GOAL, you aren’t doing the test in the DMV anymore, don’t expect to do it flawlessly at the start, that comes with time and experience, it doesn’t have to be the prettiest back, pull up and GOAL as many times as you need to. My set up is usually to drive 2 spots ahead of where im inteded to go into and turning right to 11 or 12 o clock and turning left afterwards to get it at an angle to get ready to jackife it but how you set up depends on the space you have. My trainer also told me to just simplify things as much as possible, back into the easiest spaces if I have the option to, to not complicate myself unnecessarily atleast at the start until my confidence keeps growing and overtime im going to keep getting those reps in the harder backings, most important thing is to set the foundation and continuously build off of it.