Another way is to make your post about the game and then at the bottom of your post is a button that says Link to Calendar, click that and it will come up looking like your making a post, but all you got to do is make sure you have it set for the correct date of the game. The Title is what will be seen on the calendar. If you have several games in one post, just repeat the process and make sure it's on correct date of game again. If you want to go back and edit your calendar entry, go to the calendar where your game is and click on the little red dot just before your game title.
Hope this helps also.
