#define BotName                    "{FF9900}Razer:"
new RandomMessages[][] =
{ // change all this Messages to your own server MSG's, TDC means Tokyo Drift Central so just change TDC to ur server name.
    BotName"Hello, Welcome to the server and enjoy your stay here "
};

under ongamemodeinit()
1000=1 second 
now what ever mins or seconds you want

public OnGameModeInit()
{
SetTimer("AutomaticMessage", 50000, true);
return 1;
}

public  AutomaticMessage()
{
    new RandomColor[] = {COLOR_RED, COLOR_GREEN, COLOR_YELLOW, COLOR_BLUE}; // Orange ( first ) and blue ( second )

    new RandomMessage = random(sizeof(RandomMessages));
    SendClientMessageToAll(RandomColor[random(sizeof(RandomColor))], RandomMessages[RandomMessage]); // -1 is a colour for a message.
    return true;
}

SetTimer("AutomaticMessage", 50000, true);

new RandomMSG[][] =
{
    "1: ..",//This is the first message it will send,You ca change it to any thing you want.
    "2: ..",//Second Message
    "3: ..",//Third Message
    "4: ..",//Fourth Message
    "5: .."//fifth Message
};
forward SendMSG();
public SendMSG()
{
    new randMSG = random(sizeof(RandomMSG));
    SendClientMessageToAll(-1, RandomMSG[randMSG]);
}
//under GameModeInit()
SetTimer("SendMSG", 300000, true);

OnGamemodeInit()
SetTimer("SendMSG", 300000, true);//1000=1 , 2000=2 change any min or sec