I’m picking up the backing concepts pretty well except of this alley dock is just a pain. No reference points seems working either. Any tips or ways to improve it?
Follow the trailer. If trailer gets out of line, push it back to where you want it with steering wheel. Don't hit anything.
The biggest thing is practice! If you get to a truck stop early enough just move around and practice different situations. I recently switched to flatbed as an experienced driver. So now I'm practicing with a spread axle, you never stop learning. The biggest thing is practice like I mentioned. But like x1heavy said, follow the trailer. And if in doubt get out and look, many companies preach this for good reason.
These kinds of questions frustrate me. No, your question is OK, the frustration is this is something that is somewhat like shifting. Hard to teach by writing directions. It is somewhat like the airplane analogy I have used. All a flight instructor can do is teach you the basics and stay in the aircraft to protect you and said aircraft while you master flying and the landings. To be honest I have stopped doing so. You really need to go find an old abandoned dock somewhere take some cones and practice. Some drivers have bought RC trucks and use them to practice. This is honestly a doing thing. Other than offering to actually help show you these things I can't help you. You might find some youtube videos, but at some point, you got to just do it. Oh and don't let any of these people in these forums fool you. ALL of us had to learn these backs! Most if not all did so by burning diesel!
Practice, practice, practice.... Instead of sliding into that pull thru, go around back and do a couple backs, a couple times per day for a couple weeks and you'll forget that you ever struggled with it.
After I got out on my own, I had very little confidence in backing....so I decided that on my 30 and 10 hr breaks, I would back into the first available (not blindside). And it didn't take long to conquer my fear and drastically improve my skillset.