What is the absolute fastest and SAFEST way to store coins that are currently in an exchange?
This question will come as a contradiction first..."exchange" and "safest" don't go to together
In fact, there is a way, though it is likely not what the OP actually meant to ask
A disclaimer, I didn't use this method myself but I know that other traders are using this approach (if only occasionally) and especially in circumstances like these (the coming Bitcoin split and the overall panicky sentiment). Basically, you can hedge your coins without actually having them in an exchange, though it would cost you something (not much). You use two exchanges that allow margin trading and open two margin positions offsetting each other. Since you have to provide only, say, 15% initial margin (I take Bitfinex as an example), in the worst case (exchange scamming and running away with your coins), you will lose only as much. The advantage is two fold, first, you insure yourself from price volatility and, second, you don't have to keep the bulk of your coins in your exchange account