When you are depending on that graph you need to have a more time so you can really manage not to lose money in trading and save some extra bitcoin in the next dont panic when the price is low wait for it always to be high again and everything will be fine.
waiting for the price to rise high sometimes just working is it does but i'd prefer to cut lose if the specific coins seems don't have a good future to prevent from having such a big lose like zcash which had been falling down recently from 1btc to about 0.3btc and that's such a pain in the ass
As I could not have separate strategy for each and every altcoin, I decided to avoid completely all unestablished altcoins. I might be missing many good opportunities too, but I am having peace of mind with respect to where I am investing for my trading. Also, I am not loosing when I am searching for making my fortunes. That might be my simple trading strategies for altcoins.