Detailed Gameknot posting instructions

Go to gameknot.com then to link on left "My Games"

On the bottom of page you will see link for "your completed games", click on this.

There on the new page you will find completed games.  Go to appropriate game and click on "pgn" on the right side.

This brings up the notation. Click on "Select All" button, Copy this, (Ctrl C)
then paste at the Group page in a posting, (Ctrl V).

If you have more than one game to do it works out well to open your
note pad and paste games there first.

In fact if you have a bunch you want to view for yourself later on a
game viewer so there handy, then save the file in note pad or in word
processing program with text file extension. 
Example:
65sq_tourney.txt. Then rename file in your file storage area (Windows
Explorer) on pc (with .pgn extension (Example: 65sq_tourney.pgn).
You can view in any game viewer that reads pgn (Chessbase,
Chessmaster, Fritz, Winboard, etc.) .