Arbitrage is a good concept and it is as simple as buying low and selling high. Essentially, you have to find something that you can buy somewhere else at a lower price then sell at a targeted at a higher price. Now, in case of Bitcoin or cryptocurrency, just the same thing applies. Though in Bitcoin, it can be difficult for you to do so as what I heard about with other people who tried doing it. You can go to Zimbabwe and sell your Bitcoin there because people in that country are buying Bitcoin at double the rate we pay here.