One new player to another

Hello fellow hatchlings, newbies, or whatever you call yourself. I generally go by "dead" as that's my most common fate in Tarkov, but that's the way of things. What I'm putting together here is my simple pointers on what I've observed so far. Little tips and tricks that I learn from my deaths. May these help you in your endeavors to extract some sweet loot.

A little bit about me. I served as a medic attached to an Army infantry unit in Afghanistan where I saw more than my fair share of combat while on dismounted patrols. I like to apply my experiences to games like Tarkov like some dudes armchair quarterback NFL games after those glory years in High School. If you haven't guessed it yet, I'm sarcastic. Hang in there while I go through these little things. Also, to those of you who have something to add, have at it! I'm new to Tarkov but not to war. Some things I advise may be my perception in Tarkov that I'm skewed on. Y'all are the vets here.

Confusion is your friend
1. By confusion I mean do not stay still, don't wait for the enemy to come to you, unless you're setting an ambush, and don't let them dictate the battlefield.
2. This also means, don't give them information. Ever noise you make is a piece to the puzzle of your location. Not just shooting, but also walking.
  1. Hint, you can be upright and slow down your walking pace with the scroll wheel. You'll see in the bottom left a little speaker icon and slider that drop. That's your noise level being produced. When in doubt, lower is better. That being said, a slow target is an easy target.
Violence of action
1. When you push, push hard. In for a penny, in for a pound. If your foot passes the threshold then you need to be in the room. Killzones are a very real thing.
2. Ammo is cheap, your life (and gear) are not. I'm not endorsing just lobbing rounds, see Rule 1.1 if you're curious, but rather once you do start an engagement don't get all panicky over your bullets. If you were low to begin with you shouldn't have engaged. If you were engaged I wish you the best of luck. Accuracy helps with this over time as you'll expend less rounds to accomplish the same goal.
Armor does not equal life
1. You only have so much blood and endurance. Armor will take damage, not negate damage. Tarkov doesn't seem to punish you too much for taking rounds to the chest if you're armor holds up but here's a hint. If you don't face the enemy with your armor they won't hit your armor. Instead they'll hit things like your nice squishy arms.
Rapid fire isn't accurate
1. This irritates me every time I see someone start spraying at me from 50+ meters away. You're wasting rounds for no reason. One, it doesn't make me duck and it shouldn't you either unless it's an established ambush. Generally being on the receiving end of full auto fire from an AK is about as accurate as North Korea's missile program. Breath, aim, shoot.
2. If you're within 50m and/or in Close-Quarters-Battle (CQB) then full auto is a valid answer. Depends on how panicky you are. Don't get grumpy though if you're seeing your rounds fly down range and the intended recipient doesn't die. You probably missed.
Sustenance
1. So I actually just died in a match because of this and I may be a bit sour so it's going on my list. Food and water. It's said the infantry can survive on just beans and bullets. It's all we need. Implied is water, as you can't make beans without water so… yeah. These three things will see you through any battle. Failing to have one of the three will spell your doom. In my case, getting two good kills from a duo, looting four rifles and tons of gear, then proceeding to starve to death trying to find that extraction point I would have sworn was somewhere over here…
2. Paraphrasing /u/Kiratze here, but if you're gonna go on a long hike you should bring nutrients. Nothing sucks more than viewing the rising sun over the bodies of your enemies on an empty stomach with your life dropping through your drawers like water down the back of Dizzy Flores. If you take a gutshot you'll feel the pain for sure. So, bring a snack and a little something to sip on.
Fear Of Missing Out (FOMO)
1. That Mosin's looking mighty fine but an ADAR 2-15 just came in from a Scav run and you just gotta upgrade you know? Let me ask you this. Why? Some guns are better depending on your play style so you can swap out whatever name for Mosin and ADAR 2-15 you want. The point is, why fuck with what works? If you want to tinker and try new styles then cool. But coming in brand new I advise against a plethora of guns. If you want to tinker, use offline mode first and if it doesn't work out, sell the gun. Don't risk a new toy on a raid when you have no idea how it handles.
Scan your surroundings
1. Some players have an eagle eye for spotting my precious dome popping up to say hello to the world. It happens, you'll get domed, and you'll learn not to poke your head out. That's not the point. If you don't know where the enemy is, it's a moot point. Now, if you know their location and insist on poking your head out then vary it up. Left, right, crouch, move locations. Whatever works best for the situation. See Rule 1.1.
The Mad Minute
1. I love this one. Someone shoots at you and you proceed to panic. It's to be expected, lead hurts and I'm told it's toxic. Well, take that panic and put it to good use by clicking that pointer finger like a mad man while looking in the direction of your aggressor who's fucking up your day. This plays on your fight-or-flight response. Why not both? Take cover and put lead down. This may conflict with Rule 4 in general, but this is to make someone flinch. Not everyone will, but any advantage in a battle should not be wasted.
An honest fight is a losing fight
1. I'll see you at noon, in the street, with only pistols. Uhh… yeah, sure. You know what honor is for? Getting stabbed by someone without it. Now, this is only a game and we can have fun, partake in shenanigans, even send SoS with my stupid Scav's pistol light that I spawned with because that sounds like a fun challenge. At the end of the day though, will you die to be the good guy or kill to be the victor?
2. Note, this does NOT apply to groups. Team killing is a very real issue in Tarkov. Be wary of it, join with people from Discord if that's you're thing. I honestly play solo so I haven't seen it myself, I've just read Reddit like you probably have. Don't be that guy. Friendly fire isn't.
Cover vs. concealment
1. This is a simple concept that often misunderstood. Cover means the object will, in theory, stop whatever's coming my way. Concealment just means it will block line of sight and obscure my position. Hiding in concealment does NOT mean you can't be shot, it's just harder. Hiding on cover will generally also be concealment but don't trust in that. Your duck walk may lead to a rifle barrel poking out. You're covered, not concealed.
2. This is particularly comical when someone forgets to back up off the door they're camping. Your barrel is an object I can see. It doesn't end .02mm from your face. If I see a barrel poking out I'm going to back away and either frag your position, if I have one, or flank around and use concealment to cover my approach until your cover is null and void. In the Army we'd just grab it and yank you out the door right before putting rounds into you or detaining you, really depended on how strong of a grip on the trigger you had.
Have fun
1. I can't stress this enough. It's a game. I personally treat every death as a failure in my training and/or ability to remember the training. I could go on and on for days about tricks, tactics, and skills that may help but really a lot of it's real world stuff. That doesn't mean I don't have fun though. Nothing is quite as satisfying as putting rounds down range and watching the bodies drop, surviving an ambush against all odds, or winning an CQB fight with a Mosin against two dudes rocking kitted out AK's and full L4 armor.