[int3s0]

pawn Код:

new DialogText[256];
    strcat(DialogText, "Text .....");
    strcat(DialogText, "text....");
    strcat(DialogText, "text...");
    ShowPlayerDialog(playerid, 1, DIALOG_STYLE_MSGBOX, "Test Dialog", DialogText, "Ok", "Cancel");

Look how I did in my admin system:

pawn Код:

new DialogText[768];
    strcat(DialogText, "{FF0000}Level 1{FFFFFF} /say /jail /unjail /freeze /unfreeze /slap /mute /unmute /jetpack /ahideout /ip\n");
    strcat(DialogText, "{FF0000}Level 2{FFFFFF} /kick /announce /drop /godmode /megajump /eject /spawn\n");
    strcat(DialogText, "{FF0000}Level 3{FFFFFF} /goto /gethere /rape /killplayer /explode /ban /sethealth /setarmour\n");
    strcat(DialogText, "{FF0000}Level 4{FFFFFF} /healall /armourall /disarm /banip /unbanip\n");
    strcat(DialogText, "{FF0000}Level 5{FFFFFF} /setlevel /kickall /gmx\n");
    ShowPlayerDialog(playerid, 1, DIALOG_STYLE_MSGBOX, "Admin Commands", DialogText, "OK", "");

I used \n for new line