In altcoin trading determined first what kind of Alts are recommended for the long term. You should follow the coins chart and identify low and stable periods. When the right time comes, start and will sell in profit.
There are number of coins which come under the flag of altcoins and that there are only certain coins which are good enough for the sake of trading.
If you are planning of trading using your altcoins, then you need to be sure that you are choosing the right coin for trading and that you are putting in enough of the efforts which can then help you in having some good amount of profit which you are expecting from it.