Directions for multiplayer activation: Go to CJ's house, turn around and go straight down the street, and shortly after the overpass you will find some sandy looking buildings with an unusually large lot of land to the right of it. Just look in the midst of the buildings and you will see a red, hovering icon. Walk up to it, press any button on the controller of the person you want to have play with you, and go on from there. There are about three, maybe four other spots like that in the game that have different characters for the 2nd player to select, but you could just look up a special map for that. If this did not help you, look up a map anyway.