saw some good videos about backing up on jimscee youtube channel

I had the best instructor when I took my course.
He had taught me to use my landing gear when backing up to park (left to right, right to left and hold it). Although I was fortunate enough to have experience with a horse trailer for many years, this defiantly clicked and made life easier when he explained that when your backing and see the back of the trailer coming in you just turn the wheel in with it to counter the direction back the other way.
My instructor made us do backwards figure eights into a C side back up, also preforming a straight line back and a blind side in two directions in one maneuver. That was our passing for the yard test. If thats how you explain it. It was tough but very helpful for any situation. You should know backwards just as well as forwards was his motto! and he is very right.
it comes left.. you go left.. it goes right.. you go right...
This helped me out alot!!!

Practice, practice, practice is the best way to get better BUT a lot of the old timers on here seem to give the same advice the instructor seems to have given you Autish, use the landing gear as a focal point. Can't forget to watch the rear of the trailer too, this is where practice comes in and taking it slow-n-easy while backing up.

Well it is nice advice. Thanks for sharing.

That petty much sums it up. The more times you back up the better you will get.