[C#] Need draw a text string to a process game window

See more:

C#

WinForms

graphics

API

hooking

Im trying to make a plugin for Age of Empires (AOE). I want to display a message on screen of game when im playing I think must use SetWindowsHookEx and draws overlay in response to WM_PAINT messages. But im not strong with Hook. Im searching for a simple code snippet which can help me draw a text string to AOE game window (while playing game). Please help me. Thanks!