Games : How can I easily rank up?

I am rank 6 now and I want to rank up, I want to be rank 50 to call muggers on my friends (lol).

Which missions earn the best RP? I tried the heists but someone makes a mistake and everything goes off, for example, one time I couldn't take the plane to the airport in time. Another, I broke the plane. Another, some stranger died and finished our team lifes.

I need a easy to play, fast and popular mission for GTA Online, which gives a lot of RP and money (spent the $1m lol)