One of the main themes for San Andreas revolves around the Grove Street Family gang, their fall from power, and their rebirth. Thus, it’s only natural that you will do battle with other gangs in the game. While fighting these other gangs, it would be helpful to have some of your own members helping you. You can recruit your fellow gang members, with the game giving you a brief tutorial very early in the main story. First and foremost, as you know your gang colors are green, you will need to find fellow members that are wearing green. If they are standing around and doing nothing, then they can most likely be recruited into joining your immediate crew.
The number of gang members you can have following you is directly tied to how much Respect you have. At the beginning of the game, you can only recruit one or two gang members, but when your Respect is high enough, you will be able to recruit a maximum of seven members. Of course, bringing seven people along with you is troublesome, as only the Coach vehicle is able to hold all seven. Most normal cars will only be able to bring along two to four. There are only two simple commands that can be given to your fellow gang members, which is to follow you (Up on the D-Pad) or to stay still (Down on the D-Pad). If you hold Down for a few members, then your group will be disbanded.
Gang Warfare is first introduced in the Doberman story mission and you will be able to participate in it after completing it. You will notice that there will be areas of the map that are colored, with Ballas being purple and Los Santos Vagos being yellow (naturally, green is your territory). In order to start a gang war, you will have to go to an enemy territory and kill three rival gang members. This will trigger an on-screen message that a gang war has started. Also, the area will begin flashing red, which means that the gang war is in progress. The intensity of the color indicates whether there will be a lot of gang members in the territory or not.
In order to win the territory from the enemy gang, you will need to defeat three waves of enemies, with them having increasingly more powerful weapons. It is imperative that you take cover on the second and third waves, as you might see some enemies wielding MP5s or AK-47s. After defeating all three waves, the territory will become part of the Grove Street Families, turning green and causing your own gang members to start walking around it. As you take over territories, you will gain more Respect and will begin accumulating money in front of your house, as a pick-up.
Once you have some territories under your command, you will find that enemy gangs will attack those territories. If you ignore it, then the enemy will regain control of that area after some time has passed. Should you wish to defend it, go to the territory in question and you will have to defeat a single wave of enemies to fend off the attack. Note that the only territories that can be attacked must be adjacent to an enemy one. If you control all territories, then there will be no enemy gangs trying to reclaim your territories. The only way to avoid having to defend the territory being attacked is to either save your game at a safehouse, start a side mission, or die/get arrested. Also, if you’re not in Los Santos, it is highly likely you won’t have one of your areas be attacked.