1. Stealing cars is a fundamental aspect of the game (you know, hence the name of the game). However, there are smart and not-so-smart ways to boost cars, and it's important that you keep the proper methods in your head as you play. Generally, you'll want to, at all costs, avoid cops. That means that if a cop is in your vicinity, you'll want to wait for the cop to leave before stealing a car. Stealing cars around a cop will automatically draw attention to yourself. Also, preference should be given to stealing parked, abandoned cars as opposed to manned cars. This avoids the chance that you commit any more crimes as you steal the car, which will generally not be desirable. Breaking a window and hotwiring a car is easier than stealing a manned car and killing the driver in the process, after all.

2. Niko won't heal himself, so if you take damage during a mission, that damage will stay with you indefinitely until you do something about. The easiest way to cure what ails Niko is to feed him something. Find a hotdog vendor on the streets, or head to a fast food joint or a restaurant. At these places, you can find various foods that will heal Niko. By following a regimen of eating regularly, you'll allow Niko to stay at his healthiest for the duration of the game.

3. Armor allows you to effectively double the amount of damage you can take from firearms. And since damage in the game will be mostly dealt with firearms, it's incredibly important that you wear armor when it becomes available to you. You can buy it for a pretty penny at some shady establishments throughout Liberty City, but you're better off finding it at random locations in the city and revisiting those locales as you need to re-up on spent armor.

4. Staying equipped with weapons at all times will increase your likelihood of survival tenfold. It's important to try to have a variety of weapons at your disposal, too, so you can approach situations from various angles. For instance, having a baseball bat, pistol, uzi and shotgun will allow you to kill enemies in all sorts of useful ways, from the monotony of a melee attack to the pleasure of a multiple-kill shotgun blast. Remember that if you're arrested, you'll lose your weapons, but they're easy enough to replace. You can use earned cash to buy them, or better yet, collect weapons from downed enemies.

5. Building relationships in GTAIV is an integral part of the game. Without properly building relationships with the people you meet, you're missing a huge part of the game.Be sure to take up your friends' requests to hang out with them, and try to cater to what they like to increase their fondness of you. You should also reciprocate with calls of your own to hang out. As far as women are concerned, you should definitely pay attention to your relationships with them, but be responsible! There's nothing a woman dislikes more than an overly-aggressive man. Well… most of them, anyway.

6. Liberty City might not be as vast as San Andreas, but there's a lot more to see, believe it or not. There are few areas of Liberty City, if any, that are empty. There's something happening everywhere, and there's a lot to see. Take the time to explore the various boroughs and find out what they have to offer you. Not everything is immediately available, of course, but enough is from the beginning that you'll find things worth seeing if you take the time to look.

7. Remember -- you're playing as a hardened criminal, not a law-abiding citizen. You do anything wrong and a cop sees it, and you're gonna be in trouble. GTA games are notoriously fun when you have it out with the cops, but don't get out of control, especially when you're in a mission or you haven't saved in a while. You can kill whoever you want and do whatever you want as long as it's not excessive and not in front of a cop. You break either of those rules, and you're in for a chase of varying degrees. Remember that it's better to be killed than to be arrested. Being killed will make you lose cash, but you'll retain your arsenal. If you're arrested, you'll lose your weapons… and your pride.

8. Whether or not you have auto save enabled or not, you should still manually save often by visiting your safe house from time to time. Auto save is a great feature, but don't trust it. Before you shut off your game after a lengthy session, be sure to do a "hard" save before shutting your game off. It's better to be safe than sorry.

9. There are numerous mini-games in GTAIV that should be explored. In fact, many of them, such as bowling and darts, are introduced to you as part of the relationship mechanic of the game, and are great places to bring friends and dates alike. But they're also just fun to play. Take the time to stop by the pub and chuck some darts, or go to Memory Lanes and bowl some frames. As with all GTA titles, it's the stuff that's not mandatory that gives the game its depth and replay value.

10. Finally, we'll leave you with this pearl of wisdom. Money isn't exactly hard to come by, but there's not millions of dollars just lying around and waiting to be picked up. If you need cash, there are two great ways to make it. The first is to do jobs for your friends, such as doing cab rides for Roman or delivering drugs for Little Jacob. The second, more annoying and difficult way to collect money is to kill citizens on the streets. The amount of money they carry is random (if they're carrying any at all), and this is a great way to draw unwanted attention to yourself, but hey… desperate times call for desperate measures.

*credits to jahnoodles*