I'm sure most of you folks who have been doing this for a while have your own tips and tricks, but thought I'd share what worked well for us to back into a camping spot in the dark.
Knowing we were going to arrive after dark to a back-in site on our first trip last weekend, I planned ahead, and made sure I had my kids' LED Wands in the truck with me. We also have walkie-talkies to communicate with each other, but wouldn't you know it one of them stopped working just as we went to pull out on the road. I fiddled with it while we drove with no luck.
We have 3 of the older version of these:
3-in-1 LED FlashStick. So I put one where the back corner of the camper should end up, so my husband could aim for it from the truck, and used 2 to direct him. Worked like a charm. 1 arm out to indicate he needed to turn in that direction, both arms at my chest for straight and arms down for stop.