To be profitable and not worry much you should long-term trading because bitcoin's fluctuation in very high
Of course, for good coin, But if it is a shit coin, it should be done as soon as possible
I agree with what you said about doing long term trading with good coin due to a lot if shitcoin we have lately in the cryptocurrency market but my advice to newbie is that they should good for long existing coin with good historical data since it will be hard for them to choose good coin.