Create Molotov cocktails, not health kits Rather deviously, both health kits and Molotov cocktails are crafted using the same items. I'd recommend very rarely creating health kits or healing. Why? If you find yourself limping through a scenario, it might be better simply to die and/or restart the checkpoint. You can do so easily from the Start menu, and there's often no loading involved with restarting. You'll also discover that your health regenerates between certain chapter breaks, so stockpile and use as many Molotovs as you can. Bloaters are especially weak to Molotovs--some of them can die after getting hit by just one. Upgrade Listen Mode and shiv abilities first You'll find pills hidden in the environment that will let you upgrade Joel's abilities. While it may be tempting to increase his health, the most valuable upgrades are Listen Mode and the shiv abilities. As explained earlier, if you're struggling through an encounter, it's better simply to restart. Health should be the least of your worries. Instead, upgrade the abilities that will prevent you from losing health in the first place.
Molotov cocktails are incredibly useful
Always have a shiv crafted Shivs can be used to silently take down Clickers and can also be used defensively if you've unlocked the "shiv master" upgrade for Joel. However, the main reason why you'll want to have a shiv on-hand: some doors can only be unlocked with one. These locked doors usually hide valuable gear and pills for upgrades. If your inventory only has one shiv, don't waste it in combat. You may regret not being able to unlock one of these bonus doors. Master the bow & arrow This is probably the most important weapon in your arsenal. When used properly, the bow is a silent weapon. If you get a clean headshot, you'll also be able to retrieve the arrow from the body, meaning you won't have to worry as much about ammo. It can be a bit tricky to aim, although upgrading the bow with parts will certainly make it easier.
You can turn off Listen Mode if you want to but...
Focus your weapon upgrades Even if you scavenge the environment perfectly, you still won't have enough parts to upgrade all of your weapons. Instead, focus on the ones that you'll use the most. I found myself relying on the shotgun for its close-range power and the rifle for its long-range accuracy. By game's end, you'll probably be able to upgrade three weapons to their maximum. Run away If you can break line of sight of any pursuers, there's a good chance you'll be able to regroup and gain the upper hand yet again. If you're ever spotted or feel overwhelmed by a certain scenario, run away and hide somewhere. It's effective, even against the Infected--so long as you run far away enough. Play single-player before multiplayer All of the above tips apply to both single and multiplayer, a testament to how well Naughty Dog has translated the campaign into a competitive setting. However, you'll definitely want to get used to how gunplay works in single-player before jumping online. There's definitely a learning curve, especially if you're used to other third-person shooters.
You really should get good at using the bow