Like any good survival-horror, The Sinking City 2 will put the squeeze on you and your resources. So to help you stay afloat, here's everything I wish I knew before I first started.
1) Precision Over Panic
A typical zombie takes six bullets to bring down. Which is way too expensive considering how little you have to work with. So if you start spamming shots, you'll also quickly find yourself spamming the 'load save' button as well.
Instead, aim for weak points that randomly appear on their body. Each weak point is worth two regular shots, which means a zombie goes down in three. Clean, efficient and much gentler on your ammo supply.
Oh, and just one quick warning if you're coming from Resident Evil - the reticule closing in doesn't actually give you bonus damage. That's an upgrade you'll have to find first. So early on, treat it as a little bit of bonus accuracy, but nothing too important.
Video version of this guide (~11 minutes)
2) Can't Touch This
As you'd expect from an ability designed specifically to stop you getting smacked in the face, dodging is pretty dang useful in The Sinking City 2. And since most of your enemies are polite enough to announce when they're going to take a swing at you, it's not even particularly hard to do.
There are a couple of things to keep in mind, though. First of all, maintain social distancing. If you're standing too close to a zombie there's a chance they'll grab you even if you dodge. Not ideal, unless you're a big fan of worms in your lungs.
Secondly, dodge a bit earlier than you think. The dodge window is generous, but dodging doesn't give you invincibility frames, so you can still get smacked while moving out of the way.
It'll take you a little bit of practice to get the timing down, so if you're struggling, find a checkpoint near some zombies and see if they're up for a dance or two. A few rounds of that will get the lesson across well.
3) Melee Madness
And once you've mastered dodging, you can start getting a little more... adventurous with melee combat. Melee in The Sinking City 2 is both intentionally clunky and extremely powerful. So if you try to just spam melee attacks at an enemy, even after dodging them, your only reward will be a freshly chewed off face.
Instead, the key is to watch how the enemies react. After you evade an attack sometimes they'll end up winded, turned away from you... or straight up flattened on the ground. This is then your opportunity to do either one or two hits - depending on their reaction - before going back to the usual dodge and wait routine.
Is this something you should rely on in every fight? No. It's slow and risky. But if you're like me and you find yourself burning through ammo like a complete dumbass - knowing how to stomp zombies like you're in Dead Space will serve you well.

Melee is powerful but risky, so don't overuse it
4) Traps Rule
But do you know what the best weapon is? The one you don't have to pay for!
So whenever you see traps or environmental hazards like conveniently placed explosive barrels - you know, the stuff we all have in our houses - try to bait enemies into them. And suddenly a fight that would've taken a dozen bullets can be handled with one shot, or maybe even zero.
But more importantly, don't be afraid to backtrack. This is a survival-horror game, so resource management is the name of the game. If you have to run back 10-15 meters to make use of a trap, do it. It'll save you precious ammo, which means you'll have a lot more to burn in a blind panic later!
5) Crowd Control
Every once in a while, The Sinking City 2 will decide you're having too much fun and throw a small army at you. Often from different angles, which makes all of the usual strategies kinda... messy. So what's the solution?
Simple - disengage. Figure out where the zombies are all coming from, and then run towards whatever corner of the room that's safe. You might have to pull off a couple of risky dodges to get there, but that's still a lot better than being encircled.
Because once you get all the zombies packed into one big conga line, their numbers will become meaningless. In fact, they'll become a problem as the zombies will start bumping into each other rather than trying to cleave your ears off. Which then gives you the perfect chance to turn the monster mash into a series of one-on-one duels where you're always going to be favored.

Conga lines save lives
6) Cardio Beats Zombies
But sometimes a situation is just so doomed and desperate that there's no real point in fighting. Even if you somehow win you're going to find yourself with so little health and ammo that you're basically a dead man walking. So instead, use the tried and tested combat strategy that has worked wonders throughout all of human history: fucking RUN!
You're faster and more nimble than most of the zombies. So just leg it. Dodge and weave around scenery so they can't attack you, and then make a beeline for the nearest door or saferoom. While they will chase you for a little while, they're usually shy about entering new areas. Even as zombies, they apparently still respect personal space.
But this isn't just advice for those 'everything has gone to hell' kind of moments. For example, if you've already finished exploring an area, there's little reason to waste ammo cleaning up the stragglers. So just give the zombies a slip and, you know, make them the next guy's problem!
7) Trust the Map
Much like Resident Evil, the map in The Sinking City 2 is your best friend. It not only gives you the lay of the land, but it also tells you which doors are locked and why, which objects are interactible and - most importantly - which rooms still have stuff for you to loot!
So if a room is red, that means you've left some goodies behind. And since this is a survival-horror game where every scrap of junk is a priceless treasure, it's always worth going back to collect it.
And how do you know if you've collected everything? Easy, the room will turn blue. So if you only leave an area once the map has gone completely blue, you can be certain that you've done pretty much everything you can there. And for someone as loot-obsessed as me, that right there's a real peace of mind.

The area map is seriously amazing! Use it often.
8) Explore Everything
The Sinking City 2 has plenty of side-quests and side-areas that aren't required to complete the game. They're just fun extras with their own little storylines, challenges and rewards.
And while you can ignore them, I would strongly recommend that you don't. Not only are they a lot of fun to explore, but many of them will also reward you with some seriously useful upgrades: stuff like extra talent points or the always-welcome inventory expansion. And both of those will make your future adventures much more comfortable.
So if you're ever wondering whether something is worth backtracking for, my answer is always yes. Trust me on this, there's a lot of fun... and just kinda weird stuff to discover out there.
9) Talent Points
The perks in The Sinking City 2 range from dubiously useful to insanely powerful, like being able to craft more ammo. Now, two extra bullets might sound lame, but in a survival-horror game that's seriously tight on resources, being able to stretch your supplies a little bit further can make a massive difference.
But how do you actually get the perk points? There are two ways. Either by exploring and completing mysteries, or by correctly linking investigation files. That second part is especially important since the game will happily throw you points for even the most absurdly simple 'investigations'. I'm talking stuff like "there's literally only two things left on the board, just connect them please" kind of simple.
And most importantly - don't forget that you can swap around perks whenever you're in a saferoom. So if you're about to do a bunch of crafting, or use heals, equip the relevant perks to get those awesome bonuses - and then just swap back to your combat loadout. It's a bit cheesy, but I'd rather smell like gouda than have my face ripped off.

Even this will give you talent points
10) Which Weapon?
Usually when a game gives you a new, higher-tier weapon, it's just better than the stuff that came before it. Like if you have a badass submachine gun, why would you want to use the humble pistol?
Thankfully, The Sinking City 2 doesn't exactly work like that. Yes, higher tier weapons are more powerful, but they also take up more of your extremely limited inventory space, and require much more expensive ammo. So while you should absolutely whip them out when things are looking dicey, for your average encounter I'd recommend sticking with the basic pistol.
Once properly upgraded it's precise, hits hard, and its ammunition is by far the easiest to stockpile. It's your ol' reliable, and you should treat it with respect. It'll do its bloody work all throughout the game.
But just don't go overboard with it. When you're being swarmed from all sides, put the pistol down and just start hosing everyone down with the tommygun.

A Few Last Words
And there you have it. Hopefully this'll make your first trip through The Sinking City 2 a little less painful... well, as painless as a soggy hellscape filled with zombies can really be.
And if you have any tips of your own, or just a better way to do something I talked about, definitely share it in the video's comments. Have fun with the wormbies!
[Note]: I've also made a Detailed Review discussing what The Sinking City 2 does well, where it falls flat, and how it compares to the original game.