Finding the answers and guidance to this is a bitch, moreso than one would expect. There isn't much information on the net, and what IS on there is tends to be written by gung-ho re-up types.
So here's the deal, this is what you future Short-Timers must do. For everyone else, this is boring jargon.
Keep all your hand receipts so you don't get fucked out of money. If you loaned a buddy gear, get that shit back. I haven't turned my shit into CIF yet, and I might be paying for a few things. They say its cheaper to pay the cost at CIF than it is to buy a replacement. Either way, keep track of your shit.
180 days from your ETS date, you can get your initial ACAP (Army Career and Alumni Program) brief. This is the beginning. You can choose to continue the ACAP process for one of two reasons:
1) It helps you line up a job as well as write a half-decent resume and how to bullshit your way into saying that the one week that you "were in charge" of your peers is leadership experience, and now you are qualified to bravely lead the mail room or the McGrill.
2) It gets you out of work. Just make sure you have an appointment slip. There's a lot of useful information at these sessions, and you get to wear civilian clothes.
You can get an optional medical exam through Tricare. Your "Final Physical" is a pen and paper session with your PA, and sadly, no, it does not mean you don't have to do PT anymore. But if your unit seems to believe that it does, keep your mouth shut and enjoy shamming.
Keep sick call slips, profiles, get injuries documented, all that. Fuck that Army mentality, "sick call ranger" bullshit. They prattle on about how great the healthcare system is, USE THE MOTHERFUCKER. You might catch shit for "riding a profile" but what is your unit going to do for you two years from now? You're already forgotten, flipping burgers or roofing or marrying your boyfriend or god knows what. The reason I stress the medical issue is...
DISABILITY CLAIM. If you even remotely have a chance to get disability, take it. I sure as hell am. I paid dearly for this enlistment. Extra money for it? Put that shit in my hand. Or, be "hard" and whatnot, and enjoy your aches and pains and inability to do the things you used to, and have nothing to show for it. And for fuck's sake, if you're seeing headshrinkers thanks to your adventures with this army, you know where I'm going with this. Take advantage or don't. It isn't a moral judgment, it's common sense.
90 days out you'll be able to go to an ETS briefing. You bring the packet that the ACAP people gave you at the first brief you had there. At this ETS brief, they will take that packet and wonder why you don't have a shitload of other forms. You'll get those as you can. On to that.
There's a mandatory one-on-one with a reserve career counselor. You have to go. Keep the paper he/she gives you that proves you went. You need that, a copy of your ERB (update it, fuckstick, and make sure your deployment(s) are on there), your life insurance forms, the first three pages of your contract (don't worry, no matter the case, you can get them), and your leave form if you're taking terminal leave.
Getting this leave packet done can be a pain in the ass. During this entire process, keep hitting up your S1 and training room desk dudes. No one is going to walk you through this, you gotta chase that chicken and choke it yourself.
There's much more to it, like having your shit sent back home to mom and dad, and let them worry about where to store it for two months while you dick off, not to mention cleaning and turning in your gear, and jumping through a billion hoops and God help you if you don't have the necessary paperwork or else you gotta come back later, son.
And they told me I was an idiot for starting early. There have and will be snags and hangups. Do it as soon as possible. And never, EVER forget the Short-Timers Code of Conduct. (Stand up at a halfassed version of Attention as you read, nay, SHOUT these sacred words)
THE SHORT-TIMER’S CODE OF CONDUCT
I am an American short-timer. I serve in the forces into which I was so carelessly drafted/enlisted/recalled/stop-lossed. I am prepared to leave them at the time so designated by the Department of the Army, or sooner if at all possible.
I will never extend or re-enlist of my own free will. If I am in command, I will never allow my fellow short-timers to fraternize with the lifers.
If I am called before the Commanding Officer, I will continue to resist his re-enlistment talks by all means available. I will make every effort to escape.
If I should become the victim of an involuntary extension, I will keep the faith with my fellow short-timers. If I am the shortest, I will assume command; if not, I will obey the shortest.
When questioned, should I become the object of a re-enlistment interview, I am bound to give only my name, rank, service number, date of birth and date I am due to be discharged.
I will never forget that I am an American short-timer, responsible for my actions, and dedicated to the principles which have made carefree, happy civilians out of thousands of short-timers before me.
I'm somewhere in the whole process, so there are things I still haven't learned the hard way. Any of you ETS-successful readers out there, feel free to add to this guide. This needs to be completed, edited, perfected, and widely distributed so that no short-timer go unseperated.