1. Get a friend
2. Get your friend to host an online lobby
3. Do the single player glitch online (If you don't know how to do it, then look it up)
-Make sure you do the glitch while you are in his game, or else it will put you in a random game
4. Have your friend get 2-5 stars (Tell him to blow some cops up with a tank. That will get him 5 stars quick)
5 - Receive a mission from any of the contacts.
6 - Keep your friend in the car that has the cops and keep calling the mission over and over. So you receive the RP and Money.
-So just pressing (A)

Here's a video if your desperate...