If you want your stop-loss to be hit automatically as described in the post I recommend using different exchanges to diversify your investment so that if something happens you are not out your entire investment. If you are in the trade longer term, you can use cold storage (which is the safest way to store your coins), just keep an eye on the price, and if you notice the price go below where your stop loss was simply transfer your coins to the exchange from your cold storage wallet and then sell them.