Put your pride aside and take your TT to a big parking lot in one of those big shopping malls late in the day or in a parking lot where the stores are closed. There are always big empty areas in the back.
Practice backing up in between the yellow lines using 2 spaces back to back. Going up and down the aisles. Buy a couple of orange cones and place them in the parking and then try backing up between and/or turning around them without knocking them over, etc.
It's what I do with all my first time horse trailer customers.
Practicing in a parking lot will give you confidence AND experience BEFORE you hit the road and have try to back your rig up into a small roads and tight fitting CG site without having practiced first. :W