Reading through this thread brought back many memories of when I was learning to drive truck 25 some odd years ago. In the years since then I've seen seasoned drivers with hundreds of thousands of miles of experience that still have difficulty during backing manuevers, so don't beat yourself up if you have trouble getting it down pat. Take your time, keep your spotter in view, pull ahead if need be, and number one: the spotter's role is to keep you from hitting things, NOT to give instructions. It'll keep you from having to spend a few nights on the couch or in the fiver out in the driveway!
I was fortunate enough to grow up on a farm, so backing trailers and wagons became second nature. I even got to where I could be out in the field and back up the tractor, field chopper, and wagon fairly straight if I got into a muddy section that I couldn't get through. I was in deep doo-doo though once it started going crooked!
Once I moved up to the fiver, backing it was a piece of cake, and I was extremely thankful for the years of experience. To put my fiver next to my garage, I have to put it through an ess pattern, missing the corner of the garage roof on the right by about 4" and missing a tree branch with the left front corner of the trailer by about 4" also. I put it in an out myself, the wife closes her eyes each time I have to squeeze it in there. :-laf Naturally, if the fiver is only going to be unused for only a couple of weeks, it sits out on the driveway instead of backing it into "the hole". Why take the chance?