I can sell you a system that will work, but I'll give it away for free. If you have the means, just stay long in an equity index. Sure, they will have their down moves, but over time since their inception they keep going up. By the nature of the universe of global economics, they cannot go down and stay down for long. The real trick is knowing when to get long on the inevitable pullback.
That advice is worth $400,000,000. Please remit a check to "Hi, I'm a dumbass and I must send you my home, wife and pet dog. I love you, you have saved my life because you are a financial God and know all and I am a lowly slug which cannot think for myself."