//dont create them OnConnect as it might get the TD ids messed up, do it like:
public OnGameModeInit()
{
    foreach(Player,i)//create them here for every player in advance
    {
        Textdraw0[i] = TextDrawCreate(500.000000, 433.000000, "");
        TextDrawBackgroundColor(Textdraw0[i], 255);
        TextDrawFont(Textdraw0[i], 2);
        TextDrawLetterSize(Textdraw0[i], 0.299999, 1.300000);
        //and so on...
    }
    return 1;
}

//then just show and update them in your command like:
new ktd[32];
format(ktd,sizeof(ktd),"Kills: %d",kills[playerid]);// show what u wanna be shown, this is just an example
TextDrawSetString(Textdraw0[playerid],ktd);
PlayerTextDrawShow(playerid, Textdraw3[playerid]);

//You dont have to destroy the TDs OnDisconnect or smth., just update the TDs for the playerid as all
//TDs already have been created in advance under OnGameModeInit