A few thoughts:
1) The "move the reticle to the bullet hole" method works fine as long as you have a front rest or a bipod, and a rear bag. After the rifles recoils, you still have your original point of aim, so just realign the rifle so that it sits unassisted with the reticle resting on the point of aim again, then carefully make the reticle adjustments without disturbing the rifle.
I did this for an Asian gentleman at the range a few weeks ago who was really struggling to get the rifle zeroed. Turns out he had a lot of experience shooting in South Vietnam, but never with a scope. After 40 plus years he wanted to get back into shooting again.
2) Some folks get really confused about which way to adjust the windage and elevation on a scope and they end up having to look at the little arrow on the turret. There's no need for that. Instead just use the "right hand rule". Extend your thumb on your right hand and curl your fingers. Point our thumb in the direction you want the point of impact to move (up or down, or left or right) and then turn the turret the same way your fingers are curled.
The exception is if you have a scope made in the former Soviet Block - the adjustments work in the other direction on those so, you'll need to use the "left hand rule". That's really handy if you don't know the Cyrillic letters on the turrets.
The same left hand rule also works for metallic aperture sights.
3) What distance to zero a rifle at depends on a few things.
a) If you are using a BDC reticle, or have MOA or MIL dot target or tactical turrets and plan on making adjustments in the field, then you want a 100 yard zero. You'll then adjust up from that 100 yard basic zero.
b) For most hunting purposes, with high velocity rifle cartridges, it makes sense to zero for what ever range give you your maximum point blank range. For medium sized game that is normally defined as the range where the bullet does not rise or fall more than 5" above or below the line of sight. For varmint or small game hunting, it's reduced to +/- 3".
For a 55 gr FMJ with a 2.9" high mounted scope on a 20" AR with an MV or around 3240 fps, the 5" PBR zero range is 318 yards, and will leave you 5" high at 200 yards and 5" low at 367 yards. If you don't have access to a 300+ yard range, you can zero it 3.1" high at 100 yards.
The 3" PBR for the same load is 270 yards, or 2" high at 100 yards. That zero will leave you 3" high at 170 yards and 3" low at 310 yards.
For a .308 with a 165 gr Game King at 2700 fps and a more normal bolt action scoped rifle sight height of 2", the 5" PBR zero range is 280 yds, leaving you 4.1" high at 100 yards, 5" high at 160 yards and 5" low at 325 yards. With a 150 gr bullet at 2800 fps, the PBR zero is 285 yards - 3.9" high at 100, 5" high at 160, and 5" low at 335 yards.
c) Many hunters zero so that they are 4" high at 100 yards. Obviously that works for the .308 with both 150 and 165 gr bullets, and in fact it actually works pretty well for a number of non-magnum high velocity rifle loads (.270, .280, .30-06, etc), so if you're in doubt about the ballistics, just sight in 4" high at 100 yards and limit the range to around 325 yards.
If you're shooting a iron sighted 30-30, sight in 5" high at 100 yards and limit your range to 250 yards.
The 8" bull on the standard 100 yard small bore rifle target is ideal for the 4" high at 100 yards method as you can hold on the bottom of the bull and zero so you are hitting in the X ring.
It also works well with an iron sighted 30-30 as well, you just shoot with the front blade at the 6 o'clock position on the bull, and put the center of the group about 1" above the X on the target.
4) Assuming you will not be adjusting the elevation on the scope, and you will be shooting beyond the point blank range of the rifle, generally speaking you'll want to zero at about 85% of the maximum range you plan to shoot. That's an artifact of how the trajectory works, with the bullet dropping very quickly once you've passed your zero range.
For example if I am shooting a .308 168 gr SMK at 2700 fps, and I want to shoot out to around 500 yards, I'm going to want to zero at around 425 yards. This will leave me 5" low at about 450 yards and a still manageable 14" low at 500 yards, and about 27" low at 550 yards (call it a foot low and two feet low respectively on a deer or antelope sized critter and you're good to go).
The mid range trajectory is also about 14" high at 225 yards, and that's a reasonable amount of hold under for closer shots that might pop up. In fact I can hold a foot low anywhere from 150 yards to 350 yards and get a solid hit in the vitals with that 425 yard zero.
5) You can also establish a basic zero based on the minimum distance you plan to shoot. Again way back in the day when the .308 was used for sniping out to 800 yards, the minimum range was considered to be about 500 yards. Shorter ranges increased the chances of being detected, without significantly increasing the probability of a first round hit, for a well trained sniper. So the basic zero was 500 yards and the sniper adjusted the hold up from there.
6) It's common to zero at 25 or 50 yards, particularly if all you have are indoor ranges with those maximum distances. If you have a ballistics program and you properly enter sight height, muzzle velocity and BC, you can get fairly good data. But...the problem is that a small error at 25 yards/meters becomes a very large error at 300-400 yards/meters - by a factor of 8.
Thus if you establish a "zero" at 25 yards or 50 yards, you need to verify that zero at 100 yards or more before you actually take your rifle in the field. You'll almost always find you make an adjustment to correct it. You'll also find differences due to change in temperature and elevation, and if you flew, you'll discover the airline often isn't kind to your rifle and scope and the reticle can be jarred off target.
7) As noted in the post directly above, positon can and often does make a difference in zero. Ideally, in the field most people shoot prone, or even better off a bipod, and zeroing prone or prone using a bipod is thus the preferred method to zero. A shooter's eye is farther back from the scope when shooting from a bench compared to prone, and if the scope isn't mounted so your eye is centered on the optical axis, and you are shooting well away from the 150 yard parallax ranges most scopes intended for high power rifles are set at, you'll get parallax error.
The rifle also recoils differently in different positions, which affects the angle of departure, and thus the point of impact. When I shot service rifle with M14s and M1As, I had separate sight settings for prone, sitting, and offhand positions and had the change from the basic (prone) zero, written on the sling for the other two positions. I do the same thing now shooting 3 position small bore.
