To store bitcoin, I print 4 copies of heavily encrypted paper wallet and store it in 4 safe different locations. Its almost impossible to lose my money to a thief too, since the encryption key is only in my head and my fiat bank deposit box.

I think this method is the safest method of storing bitcoin, though it can take some time to spend it, so I would only recommend it for cold storage, such as savings or funds to be spent on a later date.