This achievement requires you to beat the game on a permadeath mode with only a single save slot (and no autosave). If you die, the save is autodeleted and you have to start over. It's not nearly as hard as I expected.
A couple of notes and hints on getting this achievement. It's not step-by-step, because that would be a walkthrough for the entire game:
1. You cannot unlock this mode until after completing the game once. Use the first playthrough to thoroughly explore, learn ways of beating different parts, doing side quests and other achievements, etc.
2. You cannot do this mode as a NewGame+, unfortunately.
3. Stick to a stealthy approach. While I'm sure someone will do it with all guns blazing, not getting into fights is an easier way to avoid death. The only weapon I used the entire game was the tranq rifle, and even that maybe only 3-4 times. Everything else was avoidance or stealth takedowns.
4. On that note, the only purchases I made the entire game were extra praxis kits and some biocells. The biocells are very nice for late in the game when you want to do long cloak runs and you can use them to keep regenerating energy on the fly. I never purchased any hacking gear, and only used a handful of them (a few nukes and one stop) in the very final missions to save a little time. Never used any medication, any grenades, or anything else. Grab easy to carry/sell items and books for the extra xp when they're convenient, but don't waste time with unnecessary exploration (that's what the first playthrough is for).
5. You don't have to do this as pacifist or foxiest of the hounds, although avoiding bodies and alarms is generally a good idea.
6. Just stick to the main missions; avoid time-consuming and dangerous sidequests. The only sidequests I did were the ones that involved getting the neurocalibrator, and in retrospect I could have skipped those as I didn't really need it the way I ended up using my praxis points.
7. I always keep a handful of praxis points unused in case of emergencies (e.g., not realizing the order I need to unlock some powers in based on the path I'm trying to follow). Invest your praxis points in at least one level of cloaking (levels 2 and 3 when you've got a nice surplus), get your hacking up to at least level 3 and a point or two in stealth hacking as well. Battery recharge upgrades are nice, but can wait until later. Basic radar upgrades (range and vision cones) are absolutely essential; lidar tracking and the enhanced vision which reveals special and hidden objects are useless.
8. Icarus Landing is critical...it allows you to move around certain areas very quickly by jumping through elevator shafts and the like and prevents you from accidentally dying if you fall off a ledge or ladder (which happened to me at least once in my first, non-permadeath playthrough). You'll also want the rebreather to allow you to move through poisonous gasses. The electricity-resistance upgrade is too expensive (requires 4 praxis points in armor which you don't otherwise need) and can be skipped.
9. Break through walls and move heavy objects are both good investments. Jump is nice, although you can get through most of the playthrough before it becomes necessary/useful so I'd hold off on this until moderately late in the game.
10. The only experimental aug I used was remote hacking, and not until fairly late in the game. As mentioned already, I never used augs like dual-takedown or armor or lidar tracking or casie, so could have just disabled any of these without bothering with the neurocalibrator.
11. For the major fork in play path, I choose the bank heist because I thought it was easier, but your mileage may vary.
12. At the end of the game, go after Marchenko first and use the kill-switch to make it easy (unless you're desperately trying to do Pacifist as well). The reason to do him first, is if you try to save Brown and the others first, you have to get by all of the mercenaries twice (coming and going), while you only have to get past them once if you start with Marchenko.
13. Save often, but carefully. Don't save in a place where you might have trapped yourself. If you set off an alarm (more often than not), you're better off reloading immediately than hoping it will go away. If you're in any danger of dying at all, reload immediately: don't be a hero!
14. As with the other endgame achievements, this one won't actually unlock until the very end of the credits, so go find something else to do for the 10 minutes they roll while waiting for it to unlock.