I have been boating for many years, and I have a pretty good routine down. I'll spell it out here, and hopefully you can learn from it.
When I get to the lake, I go straight to the boat ramp. Back down the ramp and stop at the edge of the water. That is when I start to get everything ready - you know, remove the cover, take tie downs off, load the cooler and fishing stuff into the boat. I make sure to take my time doing this, as you want to make sure you get everything right.
Once I have everything unloaded into the boat, I back it the rest of the way into the water. I then get in, and start the boat while it is still attached to the trailer. That way you know it will start and run. Don't worry about ever hooking the engine up to the muffs and the hose at home before you get to the lake. That is unnecessary.
If you are anything like me, you will likely forget the plug. So turn off the boat, pull it just up out of the water, and then let all the water drain out that filled the hull. Should only take 10 minutes or so, so there is no need to take it up to the parking lot.
Now that you have the plug in, back the trailer into the water again. Start the boat again. Let it warm up for 5 minutes or so on the trailer to know it is running strong. Once you have done this, you can move the boat over to the dock.
I like to tie up to the dock as close to shore as possible. Less of a walk back from the truck that way.
Speaking of the truck, it is now time to pull the trailer up to the parking lot. Obviously you leave your boat tied in close on the dock (engine running, stereo blasting) while you do this. Pull the truck up to the very top of the parking lot. That way you are less likely to have parking lot damage, and an easy escape once you leave for the end of the day (unless there is a handicapped spot available, then take that spot as no one ever really NEEDS those at the lake).
So, now you have the truck at the far end of the parking lot. Walk half way down the ramp before you remember that you didn't lock your truck, or left you phone up there. So walk (slowly) all the way back to the truck and check.
Once that has happened, you can take your time and walk back to the boat. No need to hurry, you don't want to over heat.
Now, you are back at the boat on the dock. If you haven't already, now is the time to put all your fishing poles together, pick out what your lures of choice is, etc. True fisherman make sure they have at least 5 rods per person, so make sure to get them all hooked up.
Now, you should be ready to head out on the water, so turn the boat around, and motor out to your choice of spot. My preferred speed, especially in the launch area, is somewhere around 2000 - 3000 RPMs. You know, enough to get the bow up, and make a nice, large wake. And get as close to those silly "no wake" bouys as you can, as the are fun to watch when they are hit by a big lake.
And remember, this advice is best to do on a busy holiday weekend. Memorial Day at Horsetooth/Boyd/Chatfield/Creek/Pueblo is the place you want to be.
Finally, if there is a storm coming in, make sure you take extra time to get everything right. No need to ever hurry.
