*This guide is written under the assumption you have not yet played the game and are starting a new game with standard, non-custom settings.
Starting Out
When you first load into the game, you'll find yourself in your bunker. Inside the bunker there's a cable, 4 garbage piles, a gasoline generator, a crafting bench, an incinerator, as well as a splitter on the wall. All of these things are very helpful but we won't worry about these at the moment. You'll notice a door at the top of the stairs leading out. Going through this door starts a time trial where you'll have 60 seconds to loot a house before you experience your first shining; an event heralded by sirens that deletes anything outside of the bunker, including players and their inventories.
While looting the house, be on the lookout for any clothing, backpacks, and weapons. The basement is a fairly consistent spot for these items, though you should have enough time to quickly sweep every room. Prioritize grabbing clothes and backpacks first as this will give you more inventory slots to store items, and if you are lucky enough to get a sledgehammer or axe in the house, make room for either of these items because they are essential later on. Be sure to check on higher shelves for items, you may need to jump to be able to grab them. Also, when finding clothes you'll need to equip them instead of picking them up because your default inventory size will not be able to hold most clothing. As a final tip, you can leave items you find in front of the door indicated by the message stating "Wait here to extract!" and they'll be brought into the bunker with you when the time is up. Be sure you're standing directly in front of the door before the time is up otherwise you will lose everything you've picked up.
Once the first shining is over, you'll load back into your bunker, right where you first started the game. You can pick up the garbage and put it in your incinerator for crafting ash which you'll need for crafting various items later. The incinerator processes a lot of important resources for you like ash and iron bars, but requires power.
Notice that the crafting bench has both an inventory grid and a separate tab for crafting. You can use this storage space for materials you find but keep in mind that when crafting in the crafting bench, the materials needed for the item you plan to craft must be inside the crafting bench's inventory, and this goes for the other crafting benches you'll come across as well.
To get your first storage container, head back up the stairs to the door you went through earlier and you'll notice it simply swings open with no loading screen, showing a helicopter to the left and some ruins to the right. This area still counts as your bunker and you can place things here, but don't be caught out here during a shining! Directly to the right just after leaving the bunker, you'll notice a cabinet you can pick up. Take this inside your bunker and place it on a wall for your first storage container. If you can't pick it up, you can still access its storage where its at and move it later when you find some clothes or a backpack. Back outside, go left and into the shed in front of the helicopter. Behind the bicycle and on the table there is a car battery, pick that up and bring it into the bunker as well. Car batteries are the early game power storage devices and will very much come in handy when expanding your power system and powering new benches and lights. You'll typically want to wait to generate power with your gas generator until you've found or crafted another cable so that you can wire up the battery between the gas generator and whatever you're powering, otherwise you may end up wasting power.
One thing to note about the bunker area is that any items, inside or outside, will not be deleted during a shining. However, players in the outside area of the bunker will die and have their inventories deleted. This means that while looting in the exclusion zone, players can quickly drop items on the floor directly outside the door to the exclusion zone inside the bunker area and not have to worry about losing them, greatly speeding up depositing items found in loot runs.
Once you've got your bunker sorted, head across the field and to the door on the opposite of your bunker. You'll notice that you have two options on the door: Expedition and Sirzez.
Expedition
Expedition is the looting phase of the game, which takes you into a randomly generated map with points of interest for players to explore and loot. Expedition maps are wiped and all items deleted after every shining or when the host quits the game. When an expedition map is deleted, a new one is generated. These maps are based on tilesets that are unlocked by progressing your shining count, which is displayed in your ESC menu at the bottom right of the screen just above the season and right below the in-game time of day.
Sirzez
This is the NPC trading hub filled with vendors who buy and sell various items for rubles. Very important and useful for progression. Noteable things about Sirzez are that the Hunter sells a decent starting shotgun in working condition for 450 rubles, the Tailor sells every tier of backpack as well as decent radiation protection gear, and the Barman will buy your grown crops and bread which is great for "passive" income while the Junk Dealer will buy various junk items found while looting as well as excess materials such as wood and gasoline. Players are safe inside Sirzez during shinings, meaning they can also use Sirzez as a slightly quicker way of returning to safety during a shining, considering its right there as soon as you return from an expedition, saving you the walk back to the bunker from the door.
Best Early Game Practices
Now that you have your bunker set up and know what's beyond the bunker, you'll want to prioritize a few things in the early game.
First, craft the "Busel" Detector as soon as you can. This device can be used to find Artifacts inside of Anomalies, which are very helpful equippables and sell for a lot of rubles. Artifacts only spawn in the dangerous anomalies as well as being invisible until you get close to the Artifact while holding the "Busel" Detector. While holding the "Busel" Detector, its meter will go higher the closer you are to the Artifact, and when you are very close, it will appear and you'll be able to pick it up. These Artifiacts can greatly increase your max health, max stamina, max hunger, and max thirst as well as increase how fast you can passively reduce your radiation levels. They often come with downsides, but some of the best Artifacts come with negligible debuffs making the positive benefits greatly outweigh the negative. You can have up to four Artifacts equipped at the same time.
Keep an ear out for wooden turbines. Seriously, they make a pretty obvious "whoosh whoosh" noise and are fantastic early game scores. These turbines can passively generate 2 power per second and require no fuel whatsoever, they just have to be placed outside. There's one specific POI that can appear in the meadows tileset that sits among a field of white flowers that has both a large farm plot as well as a wind turbine, making it one of the best POIs to find early.
Keep a stock of plastic on you in case you find a well while looting in the meadows and forest. These have infinite radioactive water which can be purified at a chem bench once you have one crafted, keeping you up on your thirst bar and helping you craft concrete for building in the bunker.
Once you have a farm plot, growing wheat is one of the best ways to generate "passive" money. All you need to do is pick up your poop, put it in the farm plot with some wheat, and the wheat multiplies. For even better profit, if you have a microwave or oven and a chem bench, you can make fresh bread from flour made with wheat at the chem bench, which sells for more rubles per wheat spent compared to selling the wheat as-is.
Keep a lighter on you if you find one. They can be consumed at campfires to light the fire, which gives you passive health regeneration while near it. This is a huge life saver early game and stands as a good practice even in the late game because it helps save on medical supplies.
Hoard ammo and the materials needed to craft it. While its easy to pass it up early on because it takes so long to get a working gun in this game, you'll absolutely wish you had picked it up and kept it early on. Even some of the best guns with the highest damage per bullet will simply eat all of your ammo with how often you'll find yourself shooting things trying to kill you in the late game areas.
Pick up clothes, backpacks, and inventory expanding accessories and place items within them to save inventory space while looting. Weight is still an issue, but at least the bigger items wont be taking up all of your space. The inventory expanding accessories like the hunter vest and soviet gear are great for this method considering how little space they take up themselves while being able to hold so much within them, plus they can be sold at the tailor for some rubles. Backpacks can't be sold and not all clothing items can be sold, or aren't worth it considering how little space they can hold such as the raincoat or athletic outfit.