You'll be introduced to the Gang Warfare mechanic early on in the game, but for most of your time in San Andreas, it (and Los Santos) will be off-limits to you. Regardless of the time, though, there are a few basics that you can apply to help you rule the hood.
First off, as you get more and more respect, you can bring along more gang members with you on your expansion missions, but whether you want to or not depends on the player. We personally found them somewhat distracting and less than helpful, and never had a problem winning territories without them, but your mileage may vary.
Beyond that, though, it's vital that you bring along the correct equipment for the job. You'll always want to head out with full health and armor, and as many rounds for your SMG and AK47/M4 as possible, as these missions do chew up the ammo. (You seem to get a small replenishment supply whenever you win a hood, though.) If you have access to one, a rocket launcher or minigun will also be helpful when dealing with the large crowds of enemies that you'll be facing.
With appropriate weaponry and good line of sight, you can often take over hoods all by yourself.
When you're ready to rumble, head out into enemy territory and look for a gang of enemy thugs. If you're in Los Santos, look for groups wearing purple or yellow. If they're wearing green, they're Grove Street Family crew, which you should obviously leave alone. Sometimes these gangs may bleed into other territories, especially where they border, so be sure you're hitting the right target. Note that gang groups can be somewhat hard to find; if you don't see anyone on a given block, jack a car and start circling it. A group will eventually spawn in if you're in enemy territory, but it can take a few revolutions.
All you need to do to start a gang war is kill three opposing gang members; after that occurs, you should get a popup display letting you that it's on, baby, it's on! When you do, take a note of what portion of the map is flashing, then head for the middle of it. Eventually, you'll spot enemies spawning in, usually in two small groups.
The most important part of actually killing enemies actually comes before they even appear, though; you need to be sure that you have plenty of space around you on all sides. Intersections are great for this purpose, as you should be able to spot enemies coming at you from a ways off; hills, rooftops, or other high places are good, as well. If you stand near a wall or a corner, then the enemies will often flood around it in quick order, presenting more targets than you can deal with. If you can spot them coming a ways away, though, then you can use your AK47 or M4 to good effect; just click L1, fire at a target until it goes down, then repeat. When they start getting close, switch over to your Uzis or SMG and repeat the process. If you're good, you won't get hit at all, but the fact that you usually have to deal with two groups can complicate things a bit; when you note them spawning in, you may have to reposition yourself if you think you'll get hit by both groups at once. Ideally, you should be in a spot where one group will reach you first, allowing you to kill them, then deal with the second mass of foes.
In addition to the enemies on foot, you'll usually have an enemy car slowly moving around the area. You aren't required to destroy this, and should concentrate on the foot soldiers, but be aware that the passenger inside the car will try to drive-by you if you get too close. If you feel like it's a threat, you can use your M4 to shoot it in manual mode and destroy it, but be sure you do so in-between waves of enemies.
In between waves, you may notice pickups appearing around the contested territory; armor and health appear in equal measure, allowing you to replenish your life without tracking down pickups around the map. These will also let you move from territory to territory without saving, if you want to.
One thing to note is that the AI for the enemy bangers is sometimes broken, and will run away from you, instead of towards you. If this occurs, catch up to them as quickly as possible, as they will sometimes run far enough away to cancel your territory takeover. You can leave the contested territory if you must, but if you move too far, it will automatically revert to your enemy's control.
In addition to capturing new territory, you'll also sometimes be called upon to defend one of your territories that's under attack by an enemy gang. These appear on your screen as little airplane-thing icons that flash; when you spot one, head towards the icon. When you reach the zone, you'll have to kill off a dozen or so enemies; they usually spawn in between a couple of cars in the middle of the street, which will give them a bit of cover from your fire. If you have a minigun or rocket launcher, then, try to blast the cars first, as this will usually send the bangers flying.
After you kill all of the invading gang members, you'll retain the territory. If you choose not to defend it, or are unable to get there within a certain amount of time, you'll lose the territory and CJ will lose a bit of respect. Fortunately, you have around five minutes of real-world time before this occurs, which should let you reach a hood under attack from pretty much anywhere in the game world.
In addition to the clothing that you can buy from the various clothing stores in San Andreas, CJ can also find a few different costumes to wear during the course of the game. Here are some of the known costumes; there are likely more hidden away in the game.
|Valet Outfit||Unlocked in a core game mission in San Fierro.|
|Gimp Suit||Unlocked in a core game mission in Las Venturas.|
|Croupier Uniform||Proceed along Millie's relationship path until you get the keycard for Caligula's Casino.|
|Cop Uniform||Get to 100% Relationship with Barbara.|
|Medic Uniform||Get to 100% Relationship with Katie.|
|Racing Uniform||Get to 100% Relationship with Michelle.|
|Pimp Outfit||Get to 100% Relationship with Denise.|