The Golf Club

While technically accurate, the other solution is not overly helpful unless you already have 3 friends in-game. Here's how to get there if not.

* First, start a round of golf.
* To find some "friends", select "Change Rivals", then "Global Recent". This will give you a list of people who have recently completed a round.
* Press to bring up the gamercard of the selected player. If they are still in-game, add them as a friend. (They don't need to accept your friend request.)
* Repeat 2-5 more times. I erred on the side of having too many friends, in case people logged out.
* IMPORTANT: Dashboard (press ) and close out the game. To do this, press the menu button on the game, and select "Close".
* Reload the game. This will refresh your friend list in-game.
* Start another round of golf.
* Pause and select "Active Players". This should give you a list of players you just friended.
* Press on each and select invite. (They don't need to accept the invite.)

Hope this helps!

While you are playing a round, pause the game. Go to Active Players and click on a friend's name and then click on invite to game. Repeat for 2 more players. The friends you have invited do not need to enter your game or acknowledge these invites in anyway. Achievement unlocked.

As Dwaggienite mentioned in the comments for another solution, this method is much simpler than the other listed solutions, currently, and doesn't run the risk of players logging off.

"Here's a tip, if there's noone playing, just sign in three dummy accounts onto your xbox. Add them to your main account's friend list. Then reload the game and invite. That works too."

Step by step directions are as follows:
1) Actively be logged onto 3 profiles as well as your main profile that is going to get the achievement (Xbox Home -> Move to left most tab -> Switch Profile for dummy 1, 2, 3 and make sure your main profile is signed on as well)
2) Start up the game
3*) Not confirmed but you may need to have each profile initiate the game. At the main menu of the game where you can select play, Greg Norman Chose Designer, etc., press the old back button on the Xbox controller. I switched between the dummy accounts at this point
4*) Switch back to your main profile
5) Play -> Play Round -> Select any course -> Tee Off
6) Press start -> Active Friends -> Press A on a dummy name -> Invite to Course
7) Repeat for dummy 2 and dummy 3 and achievement should unlock

Good luck and happy golfing. Thanks again to Dwaggienite for the solution! Wish I had read that before adding random people, haha...