[Denying]

I won't make it for you but I can give you the idea of how to do it.

Use your admin system as you would like and if the player is an admin at the level you would like do the following;

Get the amount of warns of the selected player.
If the amount of warns equals to 0, use SendClientMessage(playerid, 0xFF0000AA, "1/3");
and set it to 1.
If the amount of warns equals to 1, use SendClientMessage(playerid, 0xFF0000AA, "2/3");
and set it to 2.
If the amount of warns equals to 2, use SendClientMessage(playerid, 0xFF0000AA, "3/3");
and set it to 3.