When I fish by myself, I do one or two things depending on where I'm fishing.
For every situation though, I unhook all the straps except for the bow hook. I back on down, get the back into the water and unhook the bow. I tie the rope to the winch post, and back on down. The boat will only go back as far as the rope, then I slowly pull out (and I mean slowly) because you don't want the boat to run back up on your trailer. I stop and get the boat where I want it then do one of the following below:
You may want to start with a 25-30' rope, once you get used to it you can move down rope length. I use a 15' rope, so I don't get in the boat to take it off. I push the boat off, and maneuver it around to the dock if I can and tie it off. Then get in the truck and park - that doesn't take but a minute.
If it's windy, and I can't get it to the dock, I pull it out of the way of the ramp and beach it. I'll pull it up on the bank to where it won't go back in the water - and if there is a big boat coming in behind me, I'll take the anchor and throw it up on the shore while tied to the front of the boat.
If people are on the dock and they look a little shady (like my stuff looks better than theirs and they are eying it and the parking lot is a ways off) I'll still beach it.
I don't let anybody go ahead of me, period. I've waited in line just like them - and trust me, just because they have a $20-60K rig, it doesn't mean they can back down a ramp and launch any faster than you. Normally, it takes them longer - especially if they are alone. Most times if there are 2 guys, the guy who owns the boat pulls the boat with his truck... but he also drives the boat. So the guy who backs down the ramp is usually not as experienced in backing and it takes them forever.
Most people know what it's like when you get your first boat - it does take practice getting it in and out of the water. Everybody's been there, done that and most times they are graciously waiting... besides, a little humor is always good when you've been waiting a while. Trust me, they aren't laughing at you - they've been there too and just glad to see it's not just them when they started out.