[Mystique]

Umm, I won't make this long but the most common thing that you use is a variable stating what faction the player is in. PlayerInfo[playerid][Faction] == 1 means that the player is in faction 1 that for example can be the police. Then as you said you wan't faction members to spawn with a certain skin. Just do something like this under OnPlayerSpawn

Код:

if(PlayerInfo[playerid][Faction] == 1)
{ 
    SetPlayerSkin(playerid, the skin you want);
}

Just mess around with that variable and you'll get pretty far actually.