Looking For Tips On How To Jacknife a Pup/Pony Trailer Pls!

Just wondering if you have any tips on how to reverse with a pony style dump trailer. Currently driving a Tandem dump truck with a Tandem Pony trailer and so far im doing okay at the pits and im able to jack knife correctly in open areas but when it comes to the jobsite some of the areas are very tight and i cant see the end of my trailer. I normally have a spotter on the jobsite but they get frustrated when i have to pull up and correct. Heres some of the things i know and if im missing anything im looking for any tips that can help.

1.When backing up in a tight area i bring the truck close to the entrance then pull away and turn slightly to the left. that way im not backing in blind side and i can see the end of my trailer in my mirror.
2. if the angle is correct and i backup the truck with the steering wheel straight the trailer keeps turning into the driveway/lane wherever im pulling into to(because of the angle i made when pulling up). Problem here is i cant see outta my right mirror so i dont know when i should start turning the steering wheel to start correct the truck to line it up straight.
3.Usually the trailer will not correct and keeps turning so then i have to pull up once or twice and get it lined up correctly.

Its almost as if theres a point of no return where no matter what i do the trailer will keep turning and me cranking my wheel trying to follow it will not straighten out whatsoever. So how do i find this point of no return at what angle does this exist? Majority of the info in the internet and videos are related to reversing a fifth wheel truck and trailer but not much out there for pintle and hitch so i thought it would be a good idea to reach out for some help and perhaps this discussion will help someone else out in the future.

 

Thanks for the tips i guess i will have to try and just practice more. I noticed that if i need to dump my truck in a specific spot i need to make sure when reversing, that my pony stays nice and close to the previous pile or else i run out of space on the reach for the pony and am too far forward.

Ive also learned that if i have judged the space wrong i can correct by following the pony and then jacknife again last minute but that can only work if the job site is an open area. Any other tips like this would be helpful.

I will for sure try to start jacknifing on my driver side that is good advice at least i can see something! But for now i try to get a spotter but then forman get pissed because they know im a noob right off the bat so any small mistakes get exaggerated but oh well i will just have to deal with that until im good i guess. Havent been kicked off a job site yet and i have a new work site im going to tomorrow so lets see how that goes.