I hunt alone and I don't have an ATV, so it's all by hand. I have yet to shoot a big deer - perhaps 150 lb deer at the most, and that's streeeetching the truth a bit (135?). This year I bought an Hunter's Safety Systems HSS-300 Ultralight treestand safety harness. I came with a "suspension relief strap/deer drag" which is used in the case that you end up hanging after a fall (to "stand" in and take the pressure off your groin to allow blood flow etc... until help arrives) and also as a deer drag (obviously). I didn't know how it would work, but I shot two deer solo this year and found it worked SO much better than dragging by hand, as I have done in the past. Here is the strap attached to the deer, to give you an idea how to rig it up.
This strap then clips onto a loop in the harness right at your tailbone, so it makes for an easy pull with all the power of your legs without having to hurt your back etc...
Here's a little video (not very well shot - sorry - as I said - i was on my own and so I had no cameraman! ignore the last 30 seconds or so). Still, it gives you and idea how easy it is to drag a small/med sized deer over dry ground once you get him moving.

Whenever I'd get to a deadfall or other obstacle I would step over, then reach back and grab the strap, lifting the head/forlimbs up over the deadfall and then lean into it and the bugger would slide over easy enough. Even if you don't hunt from a treestand, this harness is something similar (hopefully cheaper) is a great way to haul easily.
For me, being a reluctant city-slicker, I have no-where to skin deer at home. So I have to have my ducks in a row before going hunting. I have a good relationship with my butcher, so I know where the key to his walk-in cooler is and how to turn it on if there's nothing else hanging. That way, if he's not home I can still go directly from the field to his place and hang it. I have a gambrel and hoist in the roof box of my car as well well as a field-dressing kit, a box of wet-wipes, some old clothes, a few tarps). I this case there was a big transmission tower within 100 yards of the car but out of sight from the highway (this was quite and "urban" hunt, so I prefer not to attract unwanted attention). I dragged him there - you can see the feet of it behind me in this shot
Then I hauled him up with the gambrel and gutted and skinned him. I then tied a garbage bag over his head (just in case - I live in deer tick/lyme disease country and didn't want to spread any in the station-wagon). I lowered him onto a tarp (he's skinned now - so want to keep him clean at all costs), then put on an old hoodie with the hood up and lifted him across my shoulders and carried him the last bit to the car and put him in. This part was actually pretty funny, because the last 20 feet are exposed to the highway. Evening traffic was building so I could not pick a moment when there were no cars to emerge from the woods. So, all these city folk are heading home to their semi-detached houses in their cosy subdivision, when out of the woods comes this dude, wearing a black hoodie with the hood up, carrying a skinned corpse with a bag on it's head (those unfamiliar might not recognize it as a deer - the hooves are cut off) - who knows WHERE their imagination took them. All I could think was - if I WAS a serial killer, then why am I carrying a body OUT of the woods! LOL! I managed all of this alone, but I would have to change things up a bit with a bigger deer or a longer haul. Carrying on your back, especially with skin on and with antlers, is not always the safest thing in a heavily hunted area. For this, I save up old blaze-orange dog safety vests that my dog has trashed during upland hunting. Once they're too torn up to stay on her while hunting I keep them for strapping onto a deer if I need to carry one or even just to strap over my camo backpack if I put it on and it covers too much of my blaze vest. Quartering in the field is an option. I've seen it done it for caribou and it's not that hard with basic tools, but as a non-hunter you'd want to look into this before trying it on your own. Other things to consider, which some folks have touched on above, is the temperature. Things are a lot more forgiving in terms of meat spoilage if it's 10 degrees or colder than an early-season hunt when it might be 18-20 degrees out.
Anyhow - hope you are soon to BECOME a hunter. Try it - you won't regret it. I think would be a great idea to find another hunter to show you the ropes the first few times, but there's lots of good info in this post to encourage you I think. I took the time to write this in detail because I wanted to show you that you don't need an expensive ATV or a serious off-road vehicle to hunt big game. As others pointed out above - we've been doing it for thousands of years back when "Polaris" only referred to a bright star in the north that could show you your way back to your cave!
Cheers,
-Dave