If you are constantly worried about a black swan event, i would suggest you buy out-of-money puts which are about 5% away from the market price. Do this every month. That way you are always hedged and you can sleep well at night, knowing that you are max loss is capped at 5%. 5% max loss assuming you are not leveraged. If you are 2X leveraged max loss would be 10%. Of course this would cost some money, roughly 0.5% per month or about 6% annually. If you make profits north of 20% annually, you should be able to pay that price, for the peace of mind.
Above 2X leverage, you are playing with fire. Let's you use 4X leverage, then you will have to cap your max loss at 2.5%, so that your effective loss will be 10%. Then you need to buy out of money puts which is 2.5% away, which will more than double your cost for such insurance. In those cases you would be looking at spending roughly 15% on such insurance annualy. You better make sure you make sufficient returns to justify such costs.
In my experience it's the leverage that causes people to lose their sleep, not the black swan events. You reduce your leverage and you will automatically sleep like a baby.
Not participating in the markets based on such fears is more costly than the insurance itself !
Edited by NAV, 22 October 2017 - 11:26 PM.