One example ia that,When you buy/sell via an exchange, try to use limit orders (try not to use market orders). On some exchanges, like GDAX, limit orders have lower fees than market orders. On GDAX, limit orders are free as long as they dont fill immediately. Meanwhile, market orders result in a .3% fee, which is better than the 1.4% that Coinbase charges but not as good as 0%, especially if you are day trading. If your exchange rewards you for using certain order types, aim to use them.