You’ll find that different exchanges cater to different markets. Today, most countries have at least one cryptocurrency exchange specializing in their own currency. There are exchanges that can accept New Zealand Dollars in exchange for bitcoin, for example. Other exchanges are known for certain pairs. Bithumb, for example, has particularly strong liquidity in the ETH/KRW (South Korean Won) pair at the moment (and it’s easily the most popular cryptocurrency exchange in Korea).
Know thy taxes. Speaking of legal tender like the USD, it is what you use to pay taxes. If you don’t understand Bitcoin’s tax implications, brush up on them before you start power trading. One could get them into a situation where they make money on paper, but end the year down in Bitcoin without taking their loss, and thus end up owing a bunch of money they don’t have in taxes. Those who don’t have investment experience can get in trouble if they don’t understand the somewhat complex implications of trading crypto.
Lots of traders use bots (you might want to as well if you have the chops). To the next point, lots of traders use trading bots. Some are white hat; some will try to get you to make bad trades. Keep an eye out for bots. If you are using a bot, be careful, there are bots designed to exploit poorly programmed bots. In general, if you don’t have a solid grasp of TA and crypto trading, skip the bot. They are only as useful as the strategies they run.
Mean reversion is where the investor assumes that the price of a coin will remain at an average price level over time.  Upward trends, and downwards trends, are expected to revert back to the average over the long haul. This means you need to know the charts well and be able to figure out what the average price for the cryptocurrency you intend to trade in. When the coins are less than the estimated average that is when one wants to make a few purchases. When the price is higher than the average it is expected to drop back down to the mean price and that would be the time to sell.  Of course, figuring out just when to sell is the trick, and that is where the gamble comes in.
Taking the first option listed above, which is to buy the underlying, you become the direct holder of the digital asset. Upon purchase, the cryptocurrency is sent to your bitcoin address or account (wallet) with the exchange. From there, you can transfer the crypotocurrency to any bitcoin address or wallet address using your private key that verifies you control ownership of the asset.
A small number of cryptocurrency pairs. It is true. You will not find any altcoins from above the top 20. However, Bitstamp offers in its turn the possibility to work with hybrid pairs including USD and other fiats. The exchange can be used as your pass into the world of altcoins as you may buy BTC or ETH here and then transfer those cryptos to other exchanges with a wider range of pairs, which do not support fiat money.

Disclaimer: I am not a professional (or even a veteran) trader. I am an intermediate trader with a passion for cryptocurrency. I am disclosing my own ventures in crypto because cryptocurrency trading does make up a chunk of my online income and I want to be 100% transparent with you when it comes to making money online. Investing in cryptocurrencies carries a risk – you may lose some or all of your investment. Always do your own research and draw your own conclusions. Again – this article is aimed purely at advising; draw your own conclusions on whether cryptocurrency trading is right for you.

The term “day trading” suggests manically executing on trades every few minutes. But, as many of these mistakes show, day trading success doesn’t necessarily come for finding a new potential trade every second: you might find more success simply by taking your time, finding opportunities you’re fairly confident in, and executing a couple of trades every day or two.
If you are doing any active trading, set stop losses. For any coins not in your medium or long-term holds, always set stop losses. This is important for several reasons — the most obvious is mitigating your losses. But more importantly, you force yourself to decide on a point of acceptable loss, and because you now have a reference point, you are able to measure your effectiveness to keep or adjust for future trades. Sometimes, during a market dip, altcoins can plummet, and stop losses can lead to profitability by automatically selling for fiat that you can use to re-enter at lower prices.